Insects doi: 10.3390/insects17080869

Authors: Niayesh Shahmohammadi Taegeun Song Falguni Khan Sima Majidiani Yonggyun Kim

Gene delivery to target cells is required for bioengineering or medical/agricultural applications. However, the hydrophobicity of the cell membrane always makes it resistant to polar nucleic acids. This physicochemical barrier is usually overcome by a nano-formulation to hide the polarity. This study evaluated a specific formulation called star polycation (SPc) regarding its efficacy in DNA/RNA delivery to insect cells. The delivery efficiency of the SPc formulation was assessed by transient expression of green fluorescence protein (GFP) in Sf9 cells, in which SPc formulation significantly enhanced the gene expression compared with an unformulated vector. In vivo transient expression (IVTE) was performed by injection of the expression construct with the SPc formulation into larvae of S. exigua. Fluorescence was detected in all four tissues, namely, epidermis, midgut, hemocyte, and fat body, where the SPc formulation enhanced the expression in most tissues except epidermis. Under this IVTE condition, an additional injection of SPc-formulated dsRNA specific to GFP suppressed the gene expression significantly more than the unformulated vector. The enhanced RNA interference (RNAi) efficiency caused by the SPc formulation was confirmed against four endogenous genes of S. exigua, namely, Snf7, PSMB5, vATPase, and α-tubulin, by either injection or feeding of dsRNA. These RNAi treatments were lethal to S. exigua, in which dsRNA specific to vATPase formulated with SPc resulted in almost 80% mortality through oral delivery. A similar oral toxicity by SPc-formulated dsRNA was demonstrated in another lepidopteran Plutella xylostella. The oral delivery of dsRNA was applied to control sucking insects such as aphids and thrips by spraying SPc-formulated dsRNA onto plant surfaces. The sprayed dsRNA labeled with Cy3 fluorescence was detected in the internal tissues of plant leaves, in which the penetration of dsRNA into the plant tissues was further accelerated by SPc formulation. The SPc formulation of dsRNA specific to vATPase was effective at killing the sucking insects by spraying on plant surfaces. These results suggest the application of an SPc formulation to deliver DNA/RNA to insect cells.

Insects doi: 10.3390/insects17080868

Authors: Netshivhangoni Dzulani Flexy Ntsako Mashego Mahlangu Sbusiso Khavhatondwi Rinah Mofokeng Rhulani Caswell Chauke

Background: Edible insects constitute a highly nutritious, environmentally sustainable and culturally significant food resource with considerable potential to contribute to food system transformation within academic and broader societal contexts. Although global interest in entomophagy continues to increase, there remains limited research exploring the knowledge, perceptions, attitudes and consumption practices of university populations within rural South African settings. Methods: Three concurrent cross-sectional quantitative studies were conducted at the University of Venda (UNIVEN), located in Thohoyandou, Vhembe District, Limpopo Province, South Africa. Study 1 evaluated the knowledge, attitudes and consumption patterns of edible insects among 200 students. Study 2 examined knowledge and utilisation of edible insects among 390 students. Study 3 investigated knowledge and perceptions regarding edible insects among 200 university staff members. Structured questionnaires covering socio-demographic characteristics, knowledge, perceptions, attitudes and food frequency practices were administered across all studies. Data analysis was performed using SPSS version 28 through descriptive statistics, frequencies and percentages. Analyses were descriptive only; no inferential testing, factor analysis or regression was undertaken, and the three studies are compared as a descriptive synthesis rather than pooled into a single dataset. Results: Findings across all study groups demonstrated high levels of awareness regarding edible insects, with awareness reported by 85% of participants in Study 1 and 100% in Study 2, and 98% of staff members acknowleded the ecological importance of insects. Mopane worms (Gonimbrasia belina), termites and grasshoppers emerged as the most recognised and frequently consumed edible insect species. Consumption prevalence was notably high, reported at 91% in Study 1 and 69.2% in Study 2 and 66.3% among staff in Study 3. General attitudes towards entomophagy were largely favourable, with 41% of students expressing excitement about edible insect consumption and 91.1% of staff supporting the commercialisation of edible insects. Key barriers influencing consumption included religious restrictions (25.1%, reported in Study 2 only; participants with religious dietary prohibitions were excluded at sampling in Studies 1 and 3, limiting cross-study comparability of this barrier), cultural taboos (3%), inadequate market availability and limited awareness regarding nutritional benefits. Staff members further demonstrated positive environmental and sustainability perceptions, with 84.1% recognising edible insects as environmentally beneficial and viable future food sources. Conclusions: Across three independent cross-sectional studies conducted at the University of Venda, broadly similar patterns of awareness, attitudes, perceptions and edible insect consumption were observed. Although the studies differed in sampling and measurement, they consistently suggest that edible insects remain culturally accepted among many students and staff. Nevertheless, challenges relating to nutritional literacy, market accessibility and policy integration continue to limit broader adoption. Strengthening nutrition education initiatives and incorporating edible insects into institutional food systems may enhance the contribution of edible insects towards food security, sustainable protein provision and nutrition sustainability within Limpopo Province and beyond.

Insects doi: 10.3390/insects17080867

Authors: Okan Özgül Rahşan İvgin Tunca Gonca Özmen Özbakır

While climate change is a significant pressure point for pollinators and honeybees, its long-term relationship with managed honeybee colonies and honey production remains unclear and context sensitive. This study, using FAOSTAT data from 1961 to 2024, examined the relationships between land surface temperature anomalies and the number of registered beehives, the constant-price honey production value, and the normalized honey production value per colony, both globally and specifically for 18 Mediterranean countries. To differentiate between long-term structural trends and short-term temperature relationships, correlation, regression, bootstrap confidence interval, temperature series sensitivity analysis, cross-correlation function, and normalized index analyses were used together. The study results show strong long-term co-movement between temperature anomalies and recorded beekeeping indicators at the global and Mediterranean scale in the level series; however, first-differenced (year-to-year) analyses show this association weakens substantially and, for Mediterranean honey production value, reverses sign, indicating that the level-series correlations are driven largely by common long-term trends. The relationship between temperature anomalies and beekeeping indicators shows a context-dependent structure among Mediterranean countries. The findings show that the increase in colony size does not always coincide with the increase in the constant-price honey production value per colony; in some cases, these two indicators can move in different directions. This indicates the need for an analytical decomposition of the dynamics of quantitative growth and economic production value per colony in the beekeeping sector.

Insects doi: 10.3390/insects17080866

Authors: René Rehorska Valentin Kraus Nicole Bodrik Florian Lehnhardt Mathias Hutzler Martina Gastl David Renault Simon Berner

Since Tenebrio molitor L. was approved by the EU as novel food in 2021, food safety is paramount for both chemically and microbiologically safe products. Since T. molitor larvae are reared on substrates mainly based on cereals, mycotoxins and heavy metals may represent a serious risk. However, analyses of mycotoxins and heavy metals are complex and cost-intensive procedures, which may not be affordable for small-scale farmers on a regular basis. To provide a preliminary risk assessment and to add further insights to existing knowledge, this study used a rapid screening method based on MALDI-TOF to identify potentially mycotoxin-producing microfungi. The colony-forming units (CFU) were determined, and the isolated species identified. In addition, aw-values of substrates and meal (four samples, nine repeats each) were determined to assess mycotoxin-related risks. Eight mycobionts were identified, including three potential mycotoxin producers: Penicillium citrinum, Aspergillus flavus, and Aspergillus brasiliensis. Very low CFU counts (<3 × 103 CFU/g) and aw-values (0.35–0.59) indicate minor risks. LC-MS/MS mycotoxin analysis of nine samples (varying in source and time point) confirmed concentrations below the limit of detection (LoD): 0.50 µg/kg for aflatoxins B1/B2/G1/G2; 50 µg/kg for DON/FuB1/FuB2; 20 µg/kg for HT2/T2; 150 µg/kg for NIV; 1 µg/kg for OTA; and 5 µg/kg for ZEA. Heavy metal analysis (ICP-OES/MS) of three substrates and insect meal showed that all six metals (Cd, Pb, Hg, Sb, As, Cr) were below the LoD (0.2 mg/kg), except for Cr in malt residual pellets (0.4 mg/kg).

Insects doi: 10.3390/insects17080865

Authors: María Julia Dantur-Juri Jonathan Liria-Salazar Gabriela Cecilia Flores Luciana Contreras Gabriela María Silenzi-Usandivaras Paul Leonardo Duque Raúl Ernesto Campos Ximena Pérez-Otáñez

Phytotelmata are natural water-holding microhabitats that support diverse aquatic communities, including immature mosquitoes. We analyzed the diversity, composition, and interaction network structure of Culicidae associated with two bromeliad species, Aechmea distichantha and Vriesea friburgensis, in two localities of the Yungas ecoregion in northwestern Argentina: La Florida Provincial Reserve (LFPR) (Tucumán) and Isla de Cañas (Salta). Immature mosquitoes were sampled during 2017–2018, and community structure was evaluated using Hill numbers, nonparametric richness estimators, bipartite network analysis, and canonical correspondence analysis (CCA). A total of 12 mosquito species were identified, with richness ranging from 5 to 9 species depending on bromeliad species and locality, with the highest richness recorded in V. friburgensis in LFPR. Sampling completeness ranged from 96.8% to 100%. Bipartite network analysis showed moderate connectance (0.50), low modularity (Q = 0.188), intermediate nestedness (NODF = 46.94), and low global specialization (H2′ = 0.273), suggesting a relatively generalized interaction structure. Culex coronator and Cx. imitator dominated the assemblage, while other species exhibited more restricted associations. The CCA indicated that species composition was mainly associated with bromeliad height above ground, internal water temperature, sediment, and pH. These results highlight the importance of microhabitat heterogeneity in structuring mosquito assemblages in Neotropical phytotelmata.

Insects doi: 10.3390/insects17080864

Authors: Uroš Glavinić Stefan Jelisić Marko Ristanić Đura Nakarada Branislav Vejnović Milivoje Ćosić Zoran Stanimirović

Nosema ceranae infection represents one of the major health threats to honey bees (Apis mellifera), contributing to colony weakening, oxidative stress, immune suppression, and increased mortality. Due to restrictions on the use of fumagillin and the growing demand for natural alternatives, this pilot study evaluated the potential of grape pomace (GP) extract (at a concentration of 200 μg/g) as a dietary supplement for improving honey bee health and controlling Nosema ceranae infection. Newly emerged worker bees were experimentally infected with N. ceranae and maintained under laboratory cage conditions for 15 days. Bees were supplemented with GP extract either preventively, simultaneously with infection, or after infection. Survival, spore loads, and expression of immune-, antioxidant-, and detoxification-related genes were evaluated. Results showed that N. ceranae infection significantly reduced bee survival and induced strong oxidative and immune stress responses. Supplementation with GP extract significantly improved survival and reduced spore loads in infected bees, particularly when administered preventively or at the onset of infection. The extract also modulated the expression of antioxidant-related genes, including CAT, Cu/ZnSOD, GST, and MnSOD, indicating attenuation of infection-associated oxidative stress. In non-infected bees, GP supplementation stimulated the expression of immune-related genes, especially defensin and hymenoptaecin, while such immunostimulatory effects were not fully maintained in infected groups. The findings suggest that grape pomace extract acts primarily through antioxidant and gut health-associated mechanisms rather than direct immune protection during infection. Overall, grape pomace extract demonstrated promising potential as a natural dietary supplement for improving honey bee resilience and reducing the impact of Nosema ceranae infection. Further studies with more concentrations and temporal dynamics need to be evaluated.

Insects doi: 10.3390/insects17080863

Authors: Afnan Saleh Al-Qurashi Mohammed Saleh Al-Khalifa Hathal Mohammed Al Dhafer Mahmoud Saleh Abdel-Dayem Hossam Ebaid Ashraf Mohamed Ahmed

Background: Animal venoms may alter postmortem carcass conditions and thereby influence carrion-associated insects. However, it remains unclear whether lethal envenomization affects adult Diptera as a broad assemblage-level response or as taxon-specific changes during decomposition. Methods: Fifteen rabbits were assigned to control, snake-envenomized, or scorpion-envenomized treatments (with five carcasses each). Carcasses were exposed under semi-natural conditions, until complete dryness, over 11 days postmortem. Adult flies were collected daily for analyzing abundance at total, family, and selected species levels, using negative GLMM, with carcass identity as a random effect and postmortem day as a nonlinear predictor. Results: A total of 5497 adult flies representing 13 species in seven families was recorded. Total fly abundance was similar among treatments and was mainly structured by postmortem day. In contrast, treatment-related temporal patterns were detected at finer taxonomic levels, especially at the family level for Muscidae, Ephydridae, and Sarcophagidae; and at the species level for the sarcophagid Sarcophaga argyrostoma and the ephydrid Actocetor indicus only. Conclusions: both snake and scorpion envenomization did not produce a broad shift in total adult-fly abundance, but in selected Dipteran taxa showing treatment-related responses during particular postmortem periods. These findings should be interpreted cautiously as exploratory observations rather than evidence of a robust venom effect on adult fly communities.

Insects doi: 10.3390/insects17080862

Authors: Yanbo Jia Qingxing Shi Jie Chen Guojun Qi Ting Chen

Autophagy is a conserved cellular degradation pathway that plays important roles in insect–virus interactions. In the MED cryptic species of Bemisia tabaci, cotton leaf curl Multan virus (CLCuMuV) can persist upon acquisition, yet this vector fails to transmit the virus. However, whether autophagy contributes to this antiviral response in MED whiteflies remains unknown. In this study, we show that CLCuMuV acquisition activates autophagy in MED whiteflies, as evidenced by increased LC3-I to LC3-II conversion, enhanced LC3-positive puncta formation in the gut, and dynamic transcriptional regulation of multiple autophagy-related genes. Functional investigations using RNAi-mediated silencing of Atg3 and Atg9, two essential autophagy genes, revealed that their knockdown elevated viral DNA accumulation by 1.4-fold at 48 h post-acquisition. Consistently, pharmacological blockade of autophagic flux with bafilomycin A1 led to a 1.0-, 2.2-, and 1.0-fold increase in viral loads across 24, 48, and 72 h post-acquisition, respectively, whereas treatment with rapamycin, an autophagy inducer, decreased viral DNA accumulation by 46.4% and 33.3% relative to control levels at 24 and 48 h post-acquisition, respectively. Together, these loss- and gain-of-function experiments demonstrate that autophagy functions as a host restriction mechanism that limits CLCuMuV persistence in MED whiteflies, providing molecular insights into the immune competence of this non-vector species.

Insects doi: 10.3390/insects17080861

Authors: Li Xu Ke Wang Yin Huang Yunsheng Wei Hao Yu Runqiang Liu Dongzhi Li

Trypsin is one of the major digestive proteinases secreted by the insect midgut. It plays important roles in digestion, molting, diapause, zymogen activation, innate immunity, reproduction and insecticide resistance. However, the functions of trypsin and its potential as a target for the control of Spodoptera litura, a polyphagous agricultural pest, remain poorly understood. In this study, seven trypsin genes related to S. litura development were characterized. Temporal-spatial expression results showed that the seven trypsin genes were predominantly expressed during the larval stage and mainly localized in the gut. Their expression was positively correlated with juvenile hormone titer. Oral RNAi using star polycation (SPc) as a nanocarrier showed that silencing Sltrypsin1, Sltrypsin5, and Sltrypsin7 significantly reduced larval weight and food conversion efficiency and prolonged larval development. In a field-simulating trial, when dsSltrypsin1/SPc or dsSltrypsin7/SPc was sprayed on soybean or maize leaves, it significantly delayed S. litura larval development, decreasing their pupation and eclosion rates by 37.1–42.3% and 12.7–30.4%, respectively. The overall control efficacy ranged from 48.1% to 57.4%, suggesting that Sltrypsin1 and Sltrypsin7 play important roles in the digestion of soybean and maize. Feeding on artificial diets containing dsSltrypsin1/SPc or dsSltrypsin7/SPc significantly reduced LC50 values of lufenuron, spinosad, RH-5849, and chlorantraniliprole, with synergism ratios exceeding 1.5-fold. These results suggested that Sltrypsin1 and Sltrypsin7 play important roles in food digestion in S. litura feeding on soybean and maize. They could be co-applied with insecticides to increase control efficiency, reduce the application amount and mitigate resistance to conventional insecticides.

Insects doi: 10.3390/insects17080860

Authors: Huanwen Chen Dan Xie Li Liu Lihong Jiang Xiaowei Chen Kai Ding Xinhe Yu Jia Yu Defu Chi

Under climate warming, bark beetle outbreaks increasingly threaten forest health. Hylurgops longipillus, a native bark beetle in Northeast China, causes patchy mortality in Pinus koraiensis plantations. We developed an integrated emergency control system based on host selection chemical ecology. Damage characterization revealed that adults concentrated on trees with 10–50% crown needle yellowing, and infestations expanded as discrete patches radiating from multiple epicenters. Electrophysiological and behavioral assays of host volatiles and some of their isomers yielded a highly effective attractant (69.4 adults per five-trap set over 5 d, 1.8× control) and a repellent reducing ethanol-baited trap catches by 83.3%. Emergency control techniques consisted of integrated management combining removal and safe disposal of infested trees, chemical stump sealing, push–pull trapping, and tree vigor enhancement. Three-year monitoring showed ~94% decline in trap catches, no subsequent outbreaks, and stable control. This attractant-centered, chemical ecology-based system can rapidly suppress H. longipillus outbreaks and achieve long-term management, providing a scientific basis and operational framework for similar localized bark beetle emergencies under climate warming.

Insects doi: 10.3390/insects17080859

Authors: Qihang Liu Likui Wang Fu Wang Jinhai Yang Fen Li Min Li

Light-based trapping is a promising non-chemical approach for sustainable locust management in protected agriculture. However, how polarized light properties influence locust aggregation behavior under shed conditions remains insufficiently characterized. To clarify how polarized spectral properties and polarized light configurations, namely linearly polarized light (LPL) and linear detection-polarized light (LDPL), modulate polarotactic aggregation sensitivity, and to support the development of polarized spectral trapping devices for locust control, this study systematically evaluated the responses of Locusta migratoria manilensis to violet light (405 nm) and orange light (610 nm) based on prior laboratory findings. Locusts were exposed to LPL and LDPL with different E-vector orientations (0–330° at 30° intervals) under different nocturnal illumination durations. The results showed that differences in aggregation sensitivity between the two polarized light configurations were wavelength-dependent. Under violet light, the largest sensitivity differences occurred at the 150° E-vector orientation for LPL and the 240° E-vector orientation for LDPL, whereas under orange light, the largest differences were observed at the 270° E-vector orientation for LPL and the 240° E-vector orientation for LDPL. The duration-dependent enhancement of aggregation sensitivity also exhibited wavelength-dependent temporal threshold characteristics. After 10 h of illumination, LPL induced the highest mean aggregation sensitivity at the 270° E-vector orientation under both violet and orange light, whereas LDPL produced the highest mean aggregation sensitivity at the 240° E-vector orientation under violet light and at the 30° E-vector orientation under orange light. The spectral properties of LPL did not alter the cosine-periodic response of locusts to the E-vector, with sensitivity-associated E-vector orientations occurring at 270°, 180°, 0°, and 90°. In contrast, the spectral properties of LDPL reshaped the wavelength-dependent sine- and cosine-like tuning patterns and markedly shifted the sensitivity-associated E-vector orientations, with prominent orientations of 240° and 270° under violet light and 30° and 240° under orange light. Notably, under violet light, LDPL elicited significantly stronger light-induced aggregation sensitivity than LPL, with the highest observed response occurring at the 240° E-vector orientation after 10 h of illumination. Moreover, the polarized light configuration modulated the combined effects of polarized spectral properties and illumination duration: the duration-dependent enhancement was more pronounced under orange light, whereas the overall light-induced aggregation response was stronger under violet light. Collectively, these findings demonstrate that polarized spectral properties and polarized light configurations jointly determine locust polarotactic aggregation sensitivity, with linear detection polarized violet light producing the highest induction effect under specific E-vector and temporal conditions. This study reveals the sine- and cosine-like tuning characteristics of locust responses to different polarized light configurations, together with their wavelength dependence and temporal threshold effects, thereby providing a theoretical basis and behavioral evidence for the development of efficient polarized spectral trapping devices.

Insects doi: 10.3390/insects17080858

Authors: Gamze Pekbey Güngör Karakaş

Culicoides biting midges are important veterinary vectors, yet reported distributional patterns in Türkiye may reflect both ecological structure and uneven sampling. We synthesized 58 eligible Türkiye-specific reports (50 database-derived and eight citation-traced), consolidated them into 43 study/data-source families, and compiled 1164 taxon records representing 62 taxa. The all-explicit province dataset included 33 provinces and 45 taxa, whereas the primary province dataset included 18 provinces and 43 taxa. National taxonomic sources supported 72 species within the eligible evidence chain and 74 under a later taxonomic interpretation. Reported richness was strongly associated with sampling effort (Poisson coefficient = 0.579, 95% CI: 0.385–0.773), whereas biogeographical region was not significant after effort was accounted for (likelihood-ratio p = 0.914). Jaccard PERMANOVA identified an exploratory regional compositional pattern (F = 4.388, R2 = 0.369, p = 0.001; PERMDISP p = 0.325), with turnover accounting for approximately 78% of mean between-region dissimilarity. Most richness diagnostics ranged from 54 to 64 taxa, whereas Chao2 was unstable (69.6; 95% CI: 49.5–152.0). Vector-related evidence remained insufficient for species–pathogen risk modeling. Overall, the synthesis is consistent with a Wallacean shortfall strongly associated with uneven sampling and supports standardized, biogeographically balanced surveillance to test transition-zone structure, climate-sensitive phenology and redistribution, and integrated vector-host-pathogen hypotheses under comparable sampling effort.

Insects doi: 10.3390/insects17080857

Authors: Tongyin Xie Lu Chai Ni Zhang Na Wang Xinyu Ge Chuncai Yan

Jingpo Lake in Northeast China is a vital aquatic ecosystem, yet it lacks baseline molecular data for its insects. Trichoptera (caddisflies) are excellent ecological bioindicators, but their accurate identification is often hindered by morphological similarities, life-stage limitations, and insufficient DNA barcode records. To address this gap, this study combined morphological identification with DNA barcoding to establish a local reference database. From 285 collected adult caddisflies, 105 representative specimens were selected for genetic analysis. The survey identified 22 species across 9 families, revealing four new records for China and six for Heilongjiang Province. Analyses confirmed the high efficacy of the COI marker, demonstrating low intraspecific genetic divergence (0.78%) and high interspecific divergence (17.80%), with a clear barcode gap separating all examined species. Species accumulation curves indicated robust sampling of the main genera, although expanded collection efforts could still uncover additional species. In conclusion, this study provides a valuable DNA barcode reference library for Trichoptera in the Jingpo Lake region. It establishes foundational data for regional biodiversity inventories and future ecological monitoring based on environmental DNA (eDNA) or metabarcoding approaches.

Insects doi: 10.3390/insects17080856

Authors: Luyao Qi Shizhao Xiong Yuanyuan Wei Zhengzheng Zhao Yang Ma Yan Ju Kanaji Masakorala Minmin Cai Chan Yu

Insect protein farming offers sustainable advantages in land efficiency, emission reductions, and bioconversion, yet optimizing the nutrient composition remains a major challenge for cost-effective production. This study investigates the co-regulatory mechanism between alkali-soluble protein (SpA) and the gut microbiota in black soldier fly larvae (Hermetia illucens) and their effect on protein conversion efficiency. Feeding trials with varying alfalfa/SpA ratios identified a wheat middlings/alfalfa meal blend at a (5:0 ratio) as optimal for promoting larval protein accumulation. SDS-PAGE and 16S rRNA analyses revealed a strong positive correlation between SpA and larval crude protein (R2 = 0.82). The network analysis and Pearson correlation heatmap further confirmed positive correlations among SpA, larval protein, Enterococcus, and Ignatzschineria (p < 0.05), suggesting that high SpA in the substrate was associated with the enrichment of these taxa, which synergistically enhanced proteolysis through alkaline protease secretion (R2 = 0.85) and chitinase-mediated gut remodeling. Multi-linear regression modeling verified SpA as a superior predictor of the crude protein content compared with total nitrogen (TN), improving the model’s coefficient of determination (R2) from 0.40 to 0.82. These findings highlight SpA’s higher bioavailability and its direct role in metabolic utilization. By integrating the feed composition, microbiome function, and host metabolism, this study established a regulatory network driving larval protein biosynthesis. The targeted modulation of dietary SpA content may offer a promising approach to enhance beneficial microbial communities and improve protein conversion efficiency in BSFL-rearing systems. These findings provide a theoretical basis for optimizing feed formulations to support sustainable insect protein production from organic waste.

Insects doi: 10.3390/insects17080855

Authors: Xue Yang Na Ding Lingdi Gu Can Liu Zonghua Li Xin Lu Yangyang Shi Weicheng Yang Ziye Meng Qingfu Chen Xiaona Zhang

Clarifying the immune response mechanisms of Tetranychus urticae against Isaria cateniannulata is critical for developing sustainable pest control strategies. In this study, we employed transcriptome sequencing to identify immune-related genes responsive to Isaria cateniannulata infection, followed by integrative analysis using qRT-PCR, bioinformatics analysis and RNA interference (RNAi) to systematically study the expression patterns and functions of key candidate genes. The results indicated that a total of 342 genes were significantly differentially expressed in Tetranychus urticae following Isaria cateniannulata infection, including 322 up-regulated genes and 20 down-regulated genes. These differentially expressed genes were mainly enriched in immune-related pathways, including lysosomes, autophagy, phagosomes, apoptosis and NOD-like receptor signaling. Isaria cateniannulata infection resulted in different expression levels of candidate genes across various developmental stages of Tetranychus urticae. Among these, TuAPOD and TuPLA2 were highly expressed across all developmental stages, and their encoded proteins—comprising α-helices, extended strands, and random coils—shared high sequence similarity with homologs from other arthropods. RNAi-mediated silencing of these two genes achieved over 75% efficiency at 36 h. Combining RNAi with Isaria cateniannulata treatment significantly increased mortality and suppressed oviposition, with the highest 72 h mortality rate observed in the TuPLA2 + H13 treatment group (98.33%). This study provides preliminary insight into the molecular mechanism underlying Tetranychus urticae’s response to Isaria cateniannulata infection, clarifies the key role of lipid metabolism-related genes in antifungal immunity, and further confirms that combining RNA interference with Isaria cateniannulata treatment exerts a significant synergistic effect. These findings offer new insights and a theoretical basis for developing environmentally friendly strategies for controlling Tetranychus urticae.

Insects doi: 10.3390/insects17080854

Authors: Yu Cao Keying Wang Xinshuo Hu Filippo Maggi Paraskevi Agrafioti Christos G. Athanassiou Sizhe Tao Yuqi Zhang Fanghao Wan Giacinto Salvatore Germinara Shilong Jiang Can Li

Callosobruchus chinensis (L.) (Coleoptera: Bruchidae) is a destructive storage pest, causing serious losses to stored legume seeds. The olfactory system of these insects plays an important part in assisting them locate host plants. Olfactory responses of female C. chinensis adults to volatiles of disparate bean seeds (Vigna radiata, Pisum sativum, Vigna unguiculata, Glycine max, and Phaseolus vulgaris) were evaluated using electroantennography (EAG) and various olfactometer bioassays. In behavioral bioassays, C. chinensis was mostly attracted to the volatiles of V. radiata. We detected 37 components in the volatile profile of V. radiata. Among these, nonanal (11.83%), 1-hexanol (7.35%), hexanal (5.71%), tetradecane (3.83%), and 2-ethyl-1-hexanol (3.70%) were present in relatively high contents. EAG recordings indicated that the antennae of C. chinensis can detect these five compounds, and that adult C. chinensis exhibited significant positive behavioral responses to them across various concentrations. No significant differences in the olfactory preference of C. chinensis for nonanal were observed among different concentrations, while attraction was greatest for 1 µg/µL 1-hexanol, 25 and 10 µg/µL hexanal, 25 µg/µL tetradecane, and 1 µg/µL and 10 µg/µL 2-ethyl-1-hexanol. Based on comparisons of these compounds at their most attractive concentrations, C. chinensis exhibited the greatest olfactory preference for 1-hexanol. Adult female C. chinensis can keenly perceive volatile compounds emitted by the preferred legume V. radiata via their peripheral olfactory systems, and they showed positive chemotactic responses to these volatile semiochemicals. These results provide new insight into mechanisms underlying host preference in this stored-product pest. Among the compounds tested, 1-hexanol represents a potential attractant for C. chinensis monitoring and control.

Insects doi: 10.3390/insects17080853

Authors: Vadim Iliushin Dmitry Shevchenko Irina Kirtsideli Dmitry Dubovikoff Anna Kiyashko Evgeny Abakumov

This study presents the first case of an ectoparasitic fungal infection of ants from southern Russia with the description of a new species Xenomorphomyces formicartus V.A. Iliushin & I.Y. Kirtsideli, sp. nov. of a new genus Xenomorphomyces gen. nov. belonging to the family Readerielliopsidaceae. The new species was found on Lasius distinguendus worker ants within a single nest in the Botanical Garden of the Southern Federal University, Rostov-on-Don, Rostov Region, Russia. The paper evaluates the phylogenetic position of the parasitic fungus within the Readerielliopsidaceae family based on the morphological observations and multilocus phylogenetic analysis. The family Readerielliopsidaceae belongs to the Capnodiales order, the class Dothideomycetes. Partial sequences of the loci encoding ribosomal polymerase II second-largest subunit (RPB2), 28S rDNA (LSU) and internal transcribed spacer rDNA region (ITS1-5.8S-ITS2) were analyzed. The asexual morph of X. formicartus was described. A comprehensive analysis of pathogenicity was performed using live ants, histological and micro-CT studies. The sequence data, as well as macro- and micromorphological characteristics, distinguish X. formicartus from all known species in the Readerielliopsidaceae.

Insects doi: 10.3390/insects17080852

Authors: Yu Wang Nan Wang Zhi-Da Li Chen Zhang

This study investigated whether carbohydrate source and the persistence of nutrient availability influence the life-history and reproductive performance of Trichogramma chilonis. Seven experimental treatments were evaluated: continuous supply of 20% honey–water (HWC), one-time supply of 20% honey–water with the nutrient source retained throughout the experiment (HW1C), one-time supply of 20% honey–water followed by removal of the nutrient source on Day 2 (HW1), continuous supply of 20% sucrose (SWC), one-time supply of 20% sucrose with the nutrient source retained throughout the experiment (SW1C), one-time supply of 20% sucrose followed by removal of the nutrient source on Day 2 (SW1), and a water-only control (CK). Unlike previous studies that primarily compared carbohydrate types or carbohydrate-fed and unfed parasitoids, the present study specifically assessed the importance of persistent nutrient access. Nutrient-supply treatments significantly increased adult longevity and lifetime parasitism capacity compared with the water-only control. SW1C, SWC, HWC, and HW1C showed statistically comparable longevity and lifetime parasitism capacity and performed better than treatments in which the nutrient source was removed and the water-only control. Daily parasitism was highest during the early adult period and declined with age, although nutrient-fed females maintained parasitism for a longer period. Female progeny ratio varied among experimental treatments, while offspring emergence remained high and statistically similar across the experimental treatments, ranging from approximately 85% to 89%. Overall, honey–water and sucrose diets improved the adult performance of T. chilonis without reducing offspring viability, supporting their use in mass-rearing and biological-control programs.

Insects doi: 10.3390/insects17080851

Authors: Fei-Feng Wang Xiu-Qi Zou Ming Zhong Sheng-Feng Tu Min-Er Li Wen-Feng Zhao Bao-Li Qiu Wen Sang

The Asian citrus psyllid (Diaphorina citri, ACP) is the primary vector of citrus huanglongbing and exhibits positive phototactic behavior. Octopamine (OA) is a critical neuromodulator of diverse insect behaviors, yet its regulatory mechanism in ACP phototactic behavior remains largely uncharacterized. In this study, three core genes of the OA signaling pathway in ACP were identified and characterized: the biosynthetic enzyme DcTβH and two β-adrenergic-like OA receptors (DcOctβ1R, DcOctβ2R). All three genes exhibited a U-shaped developmental expression pattern and high transcript abundance in the head, suggesting potential involvement in the early nymphal and adult stages and essential roles in central nervous system. Pharmacology assays revealed that DcOctβ1R activation by OA and tyramine induced cyclic adenosine monophosphate (cAMP) accumulation, with agonists and antagonists exerting differential effects on its activity. In contrast, no cAMP response was observed in cells expressing DcOctβ2R regardless of ligand treatment. Combined RNA interference and behavioral assays demonstrated that silencing DcTβH or DcOctβ1R significantly impairs ACP phototactic behavior. These findings revealed that the OA signaling positively regulates phototactic behavior via DcOctβ1R in ACP. This study enhances the understanding of OA-mediated phototactic behavior in agricultural pests and lays a foundation for exploring the molecular mechanisms of insect behaviors.

Insects doi: 10.3390/insects17080850

Authors: Klaudia Kőszegi Attila Sándor Takács Ágnes Balogh Gergő Kovács Viktória Szecskó János Kutas Annamária Tüh Boldizsár Vörös Ilona Tunyoginé Búzás Miklós Bíró Gábor Farkas István Farkas Kitti Marsai-Mikolics Miklós Bozsó Balázs Tóth Antal Nagy

Invasive species pose increasing threats, particularly in agriculture. Here we assess the open-field distribution, population density, and phenology of Tuta absoluta (Lepidoptera: Gelechiidae), an invasive pest rapidly expanding its range into open-field habitats in Hungary. Countrywide monitoring using sex pheromone traps was conducted at 23 sites in 2023, complemented with detailed seasonal monitoring at two locations. The results reveal a wide open-field distribution of the pest in Hungary, occurring at 21 of the 23 sampled sites. Population densities were significantly higher in highly urbanised areas, suggesting that warmer climatic conditions enhance colonisation and population growth. Continuous adult flight activity was recorded from May to December, indicating prolonged reproductive activity and overlapping generations. Based on the degree-day requirements (approx. 460 °C days per generation), five generations per year were expected and detected at two intensively sampled sites. These findings demonstrate a marked shift from the “greenhouse pest” status toward successful colonisation of open fields, supported by increased overwintering potential. The observed expansion and phenological changes indicate that the climatic conditions of temperate Hungary are increasingly suitable for the persistence of T. absoluta populations outdoors. This study underscores the growing agricultural risk posed by T. absoluta in temperate regions and highlights the importance of early detection and integrated pest management strategies for mitigating its impact.

Insects doi: 10.3390/insects17080849

Authors: Huan Dong Zihan Meng Mengyao He Yujuan Zhou Ding Tu He Wang Xian Li Yiwen Liang Wenjuan Fan Chaopin Zhu Qingyou Xia Feng Wang

Insects periodically undergo molting to replace their old epidermis for growth and morphological adaptation. Muscleblind-like (MBNL) is a multifunctional protein involved in miRNA processing. To explore the role of miRNA processing in insect molting, we characterized BmMBNL in Bombyx mori. BmMBNL exhibited spatiotemporal expression across tissues and developmental stages, with the highest levels in the epidermis and upregulation during molting. CRISPR/Cas9-mediated knockout of BmMBNL (BmMBNL-KO) caused molting defects at the 3rd and 4th instar larvae, resulting in reduced size and eventual lethality. Moreover, BmMBNL-KO individuals showed a thinner chitin layer between the new and old epidermises. RT-PCR and transcriptome analyses revealed upregulation of miR-1, miR-71, miR-263, miR-8-5p, and miR-2a-3p, which suppressed chitinase expression, ultimately leading to molting failure. This study provides novel insights into the potential correlation between BmMBNL, miRNA abundance and insect molting in Bombyx mori.

Insects doi: 10.3390/insects17080848

Authors: Yolanda Santiago-Calvo Víctor de Paz Saskia Bastin Lucian Fusu Laura Baños-Picón Diego Flores-Pérez M. Isabel Pozo-Romero M. Carmen Asensio-S.-Manzanera

Biological control using parasitoids is a key strategy for managing psyllid pests in horticultural crops. This study investigated the parasitoid complex associated with Bactericera tremblayi and Bactericera trigonica, two economically important psyllid pests of leek and carrot, respectively, in Castile and León (Spain). Nymphs of both psyllid species were collected and reared to assess parasitism; emerging parasitoids were identified morphologically and by DNA barcoding. A total of 969 parasitized nymphs were collected, from which 291 parasitoids emerged, including Tamarixia pronomus, Tamarixia tremblayi, Syrphophagus herbidus, Syrphophagus cf. taeniatus, Cheiloneurus sp. and Encyrtidae sp. Tamarixia pronomus is reported here for the first time as parasitoids of B. tremblayi while T. tremblayi, S. herbidus, and S. cf. taeniatus are newly recorded as parasitoids of B. trigonica. Moreover, the two Syrphophagus species represent the first records of this genus for Spain. The COI barcode sequences were generated for T. pronomus, T. tremblayi and S. cf. taeniatus. The parasitism rate of S. herbidus on B. trigonica reached a maximum of 23.18%. No significant differences in parasitism by Tamarixia species were observed between the two Bactericera hosts. Maximum parasitism rates recorded were 32.43% for T. pronomus on B. trigonica, and approximately 11–12% for T. tremblayi on both host species. Total parasitism of B. tremblayi in leek crops reached up to 70%, whereas parasitism of B. trigonica in carrot remained generally low and poorly synchronized with pest population dynamics. These results highlight a diverse parasitoid complex with substantial natural control of B. tremblayi and variable but lower impact on B. trigonica, underscoring the relevance of habitat and temporal factors for conservation biological control in these agroecosystems.

Insects doi: 10.3390/insects17080847

Authors: Minghui Zhao Weina Wang Hongyu Lai Lixin Zhou Qi Liao Jinxin Liu Hongning Liu Miao Ouyang Gang Ren Zishu Dong

As the global population ages rapidly, demand for safe and effective strategies to promote healthy aging grows markedly. Natural bioactive compounds, with favorable biosafety profiles and multi-target regulatory properties, have become a core focus in developing anti-aging functional foods and nutraceuticals. Amid the search for novel sustainable bioresources, insects emerge as promising anti-aging candidates for their rich species diversity, scalable production, low environmental footprint, and abundant unique bioactive components such as functional proteins and bioactive peptides. Based on bibliometric analysis of 500 eligible publications spanning two decades, this review systematically identifies 32 anti-aging insect species across seven orders, classifies their bioactive components into five major categories, summarizes green extraction technologies, and evaluates their in vitro and in vivo anti-aging activities centered on oxidative stress and inflammatory regulation, while outlining the field’s trajectory from basic mechanistic research to functional application. It further highlights core challenges including fragmented research frameworks and insufficient robust in vivo validation. Finally, it recommends integrating established food science and medical methodologies with emerging technologies such as omics, artificial intelligence, and advanced delivery systems to advance future research paradigms. These efforts could provide a strong theoretical foundation for the efficient and sustainable use of insect resources in anti-aging applications.

Insects doi: 10.3390/insects17080846

Authors: Jianying Liao Muhammad Asad Yanpeng Chang Beihua Qin Chengbin Liu Xiping Du Jinzhi Chen Guang Yang

Gametocyte-specific factor 1 (Gtsf1) plays a pivotal role in the gonadal development by transposon silencing via the piRNA pathway in Drosophila melanogaster and Bombyx mori, and is implicated in the female sex determination in B. mori. However, its function remains elusive in other insect species, including Plutella xylostella, a highly destructive pest in cruciferous crops. In this study, we characterized PxGtsf1, encoding a 27.84 kDa protein containing two conserved U11-48K-like CHHC zinc-finger domains. PxGtsf1 was predominantly expressed in male pupae, males and testes. Using CRISPR/Cas9 technique, we successfully generated a homozygous PxGtsf1-knockout strain (△PxGtsf1) with 11 bp deletion. △PxGtsf1 females exhibited normal morphology in terms of external genitalia, body weight, ovariole morphology, ovariole length, oocytes number, and internal ovarian structure, and maintained the expression levels of genes related to female sex determination and fertility. In contrast, △PxGtsf1 males displayed reduced testis size and enlarged eupyrene sperm bundles, whereas apyrene sperm bundles appeared normal. Wild-type (WT) or △PxGtsf1 females mated with △PxGtsf1 males had significantly smaller bursa copulatrix distention area compared to those mated with WT males. Furthermore, WT or △PxGtsf1 females mated with △PxGtsf1 males produced significantly fewer eggs with lower hatching rates than those mated with WT males. Co-immunoprecipitation assays revealed that PxGtsf1 specifically interacts with PxPiwi. Small RNA sequencing further showed that PxGtsf1 knockout resulted in transposon dysregulation in the testes without affecting overall piRNA abundance, suggesting that PxGtsf1 functions in piRNA-mediated transposon regulation rather than global piRNA biogenesis. PxGtsf1 is first reported to be specifically required for male fertility in Lepidoptera insects but is dispensable for female sex determination., PxGtsf1 regulates transposon homeostasis without affecting global piRNA biogenesis. These findings provide new insights into the diverse functions of Gtsf1 in Lepidopteran insects.

Insects doi: 10.3390/insects17080845

Authors: Shi-Ling Wang Yan-Hong Chen Li-Ying Yang Lian-Bing Lin Wei-Wei Li Qi-Lin Zhang

Aquatic insects are well-adapted to freshwater habitats; however, the contribution of miRNA-mediated post-transcriptional regulation to freshwater adaptation remains unexplored. Here, 12 miRNAomes for larval and adult aquatic (Aquatica leii) and terrestrial (Pyrocoelia praetexta) fireflies were generated for comparative analyses. In total, 20 differentially expressed miRNAs (DEMs) specific to A. leii were screened as aquatic adaptation-related miRNAs via intraspecific and interspecific comparisons. A functional enrichment analysis of target genes showed that these miRNAs significantly (false discovery rate, FDR < 0.05) regulate 10 pathways associated with key biological processes, such as energy metabolism (oxidative phosphorylation, 2-oxocarboxylic acid metabolism, pantothenate and CoA biosynthesis, valine, leucine and isoleucine biosynthesis, and insulin secretion pathway), defense/detoxification response (drug metabolism—cytochrome P450), neural signal transduction (serotonergic synapse and sphingolipid metabolism), as well as development and lifespan (hedgehog signaling pathway-fly and longevity regulating pathway). A miRNA–target–pathway network uncovered a broad post-transcriptional regulatory mechanism related to freshwater adaptation in fireflies. The roles of two randomly selected miRNA–mRNA pairs were validated through in vivo and in vitro experiments using miRNA mimics. The current study is the first to explore a miRNA-mediated potentially regulatory network for aquatic adaptation in fireflies and even insects, providing key insights into miRNA-mediated post-transcriptional regulation contributing to survival in freshwater environments.

Insects doi: 10.3390/insects17080844

Authors: Yuning Wang Rihui Yan Xianwu Lin Siya Ma Lijun Liu Zhihong Li

Bactrocera dorsalis (Hendel) and Bactrocera correcta (Bezzi) are two globally concerning quarantine pests within the genus Bactrocera (Tephritidae). Both species inflict severe damage on the agricultural industry and international export trade. Their distribution range has expanded due to global warming, posing an increasing threat to fruit production. Heat shock proteins (HSPs), functioning as molecular chaperones, are known to contribute to temperature adaptation in insects. However, the cold adaptation regulatory mechanisms in these two Bactrocera species remain unclear. In this study, eIF4EBP3−/− mutations were established by the CRISPR-Cas9 system in both species. The survival rate of the mutations was significantly reduced with cold treatments, and qRT-PCR analysis indicated that eIF4EBP3 regulates the expression of several downstream heat shock proteins, suggesting that it may be involved in rapid cold hardening (RCH) adaptability in both fruit fly species. In addition, this work represents the first application of the CRISPR-Cas9 system in B. correcta, which provides methods to further studies on this species. Our results provide insights into the molecular mechanisms underlying rapid cold hardening adaptation in B. dorsalis and B. correcta and a potential molecular marker for monitoring cold tolerance in field populations which could guide the development of novel control strategies that target the RCH adaptation pathways.

Insects doi: 10.3390/insects17080843

Authors: Junke Nan Maofa Yang Zhipeng He Baoqian Lyu Rulin Wang Danping Xu Zhihang Zhuo

Climate change is reshaping species distributions worldwide, making reliable prediction of invasive species increasingly important for ecological risk assessment and pest management. However, species distribution models (SDMs) calibrated with regional occurrence records may underestimate potential suitable habitats because of niche truncation. Here, we evaluated the effects of occurrence data extent on SDM predictions using the globally invasive agricultural pest Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae). Global occurrence records (1763 records) and China-specific occurrence records (946 records) were combined with climatic, topographic, and vegetation variables to construct ensemble SDMs using the Biomod2 platform under current and future climate scenarios (SSP1-2.6, SSP2-4.5, and SSP5-8.5). Model performance, environmental variable contributions, habitat suitability patterns, and centroid shifts were compared between the two datasets. The global model showed excellent predictive performance (True Skill Statistic (TSS) = 0.851, Receiver Operating Characteristic (ROC) = 0.977) with balanced contributions from multiple environmental variables, whereas the China model achieved only acceptable performance (TSS = 0.690, ROC = 0.905) and relied predominantly on Bio06. Both models consistently identified southern China and the Huang-Huai Plain as the core highly suitable regions. Future projections revealed under higher emission scenarios (SSP5-8.5), particularly toward northern and western China. Centroid analyses further indicated consistent northwestward shifts under higher emission scenarios (SSP5-8.5), whereas low-emission scenarios produced less directional and more variable centroid movements. These results demonstrate that the spatial extent of occurrence records exerts a greater influence on SDM predictions than differences among modeling algorithms. Although models of China may underestimate invasion risk because invasive populations have not reached ecological equilibrium, the spatial stability of highly suitable habitats and centroid migration direction provide robust indicators for cross-model comparisons. This study provides methodological guidance for occurrence data selection and improves invasion risk assessment and management of S. frugiperda under climate change.

Insects doi: 10.3390/insects17080842

Authors: Mohamed Ezzaitouni Tarik Chileh Chelh El-Hassan Belarbi José Luis Guil-Guerrero

The growing demand for sustainable and nutritionally optimized protein sources has positioned edible insects as promising platforms for next-generation food and feed systems. Although insect composition varies with diet, the deliberate engineering of their nutritional profiles through controlled dietary and microbiome modulation remains insufficiently characterized. This review proposes an integrative framework in which edible insects are conceptualized as programmable biological systems whose biochemical composition can be tailored through diet–microbiome interactions. Current evidence is critically synthesized to elucidate how dietary inputs, including agro-industrial by-products and algal biomass, reshape gut microbial communities and metabolic pathways in key species such as Hermetia illucens, Tenebrio molitor, and Acheta domesticus. Emphasis is placed on engineering lipid metabolism and fatty acid composition because of their relevance to human nutrition, animal nutrition, and the development of functional food and feed products. By integrating insights from insect physiology, microbiology, and nutritional biochemistry, this work outlines strategies for precision feeding and microbiome-guided interventions aimed at optimizing insect-derived biomass. Key knowledge gaps and technical limitations are also identified, highlighting the need to transition from empirical approaches toward predictive, systems-based nutritional engineering. Collectively, this review highlights the transition from empirical feeding strategies toward predictive, systems-based approaches for designing customized insect biomass within sustainable circular bioeconomy frameworks.

Insects doi: 10.3390/insects17080841

Authors: Yuling Liu Boqing Fan Yixin Ma Jianghuan Lu Liwen Yin Jiayao Xu Siwei Ye Yang Gao Bo Wang Jifeng Cai Jianhua Chen Jianqiang Deng

Laterite is an acidic tropical soil enriched in iron and manganese. It is common at tropical death scenes, yet its effect on necrophagous insect development is unstudied. We raised the forensically important blow fly Chrysomya megacephala (Fabricius, 1794) on three Hainan laterites, a yellow earth control, and a no-soil substrate. We combined larval phenotyping, inductively coupled plasma mass spectrometry (ICP-MS), and untargeted ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS) metabolomics of whole larvae sampled on Days 1–3 post-burrowing. Laterites were strongly acidic (pH 4.17–4.32 vs. 7.45) and Fe/Mn-enriched. Whole-larval Fe (~10.2-fold) and Mn (~4.1-fold; whole larvae including gut contents, as no gut evacuation was performed) were consistently elevated across the three laterites, without biomagnification (bioaccumulation factors < 1). Laterite-group larvae were significantly heavier from 106 h and shorter from 130 h of age. They entered the cryptocephalic stage at 130 vs. 154 h and pupariated 24 h earlier in shallower soil (3–5 vs. 8–10 cm). In the primary merged metabolome analysis (n = 5–6 per group; 2975 metabolites), no metabolite survived the Benjamini–Hochberg correction in any laterite comparison, whereas three did in the no-soil comparison. The level-1 candidate metabolites are therefore hypothesis-generating. Laterite thus alters larval development and whole-body metal content. This implies a potential ~1-day bias in postmortem interval estimation under controlled conditions.

Insects doi: 10.3390/insects17080840

Authors: Pinhong Zhu Ming Wei Shien Pang Zhenjie Hu Junfeng Dong Dingxu Li Haibo Yang

The hawthorn spider mite, Amphitetranychus viennensis, can damage various Rosaceae fruit trees. When using predatory natural enemies for biological control, the effects of the physical characteristics of host plant leaves (such as trichomes) on the functional response of predatory natural enemies remain unclear. We studied the functional response of the predatory thrips, Scolothrips takahashii, to feeding on hawthorn spider mite eggs on five host plants (three apple cultivars: Golden Delicious, Fuji, and New Jonagold; peach; and plum). The results revealed that S. takahashii exhibited a typical type II functional response when feeding on mite eggs on Golden Delicious, peach, and plum, which had low trichome density. In contrast, it shifted to a type III functional response when feeding on mite eggs on the two apple cultivars, New Jonagold and Fuji, which had high trichome density. Additionally, the handling time of thrips in the type III response group was significantly longer than that in the type II response group, and the egg consumption at all prey densities was significantly lower than that in the type II response group. This study indicates that the shift in functional response of S. takahashii from type II to type III was associated with an increase in the density of trichomes on the host plant’s leaves, significantly reducing its predation efficiency. This finding reveals the mechanism by which plant physical traits indirectly regulate the predation strategies of natural enemies by influencing predation behavior, providing an important theoretical basis for evaluating the pest control potential of natural enemies and formulating variety layout in orchard habitats based on functional responses.

Insects doi: 10.3390/insects17080839

Authors: Jingyu Cao Yue Zhang Jingxin Cao Jianyang Bai Chuanwang Cao Zhe Xu Ling Ma

20-Hydroxyecdysone (20E) is the active form of the steroid hormone ecdysone and is responsible for regulating insect development, molting, and metamorphosis. Infection with the entomopathogenic Beauveria bassiana enhances innate immunity and reduces 20E titers in Lymantria dispar. To further explore the role of the 20E signaling pathway in antifungal immunity, we combined exogenous hormone assays, proteomic profiling, and RNAi-mediated knockdown. In this study, exogenous hormone assays revealed that 20E accelerated the death of B. bassiana-infected larvae, whereas juvenile hormone (JH) markedly delayed it. 20E promoted larval weight gain and food utilization efficiency in L. dispar during fungal infection compared to the B. bassiana group. Moreover, the 20E + B. bassiana group significantly decreased the expression of the Toll pathway-related genes, Attacin2, Gloverin4, and Lysozyme4, while reducing hemocyte counts and Pvf2 expression. Furthermore, the 20E + B. bassiana group increased the number of hyphae in the hemolymph, but had no obvious effect on hemocyte encapsulation capacity compared to the B. bassiana group. Proteomic analysis showed that Cyp306a1 and Cyp314a1 were significantly down-regulated in L. dispar at 48 h post-infection with B. bassiana. Knockdown of Cyp306a1 delayed molting and increased larval mortality in L. dispar, but did not alter the mortality rate upon B. bassiana infection compared to the dsGFP group. Intriguingly, dsCyp306a1 + B. bassiana group had significantly increased the expression of Toll3, Toll5, Toll7, Gloverin4 and Cecropin5 compared to the B. bassiana group. In conclusion, these findings suggest that reduced 20E signaling shifts L. dispar from growth toward immune activation during B. bassiana infection. This study provides valuable insights into the 20E-mediated trade-off between growth and immunity.

Insects doi: 10.3390/insects17080838

Authors: Jipeng Jiao Wei Zhang Liang Yan Yang Zhou Shucheng Li Lili Ren Adil Sattar

Ips hauseri Reitter is the most important wood-boring pest of natural Tianshan spruce (Picea schrenkiana) forests and is listed as an A2 quarantine pest by the European and Mediterranean Plant Protection Organization (EPPO). Because the beetle is small and cryptic and its immature stages cannot be reliably identified by morphology, a rapid molecular identification method is urgently needed. Here, we targeted the mitochondrial cytochrome c oxidase subunit I (COI) gene, designed a set of I. hauseri-specific LAMP primers, and established a visually interpretable LAMP assay using a WarmStart colorimetric system. The optimal reaction conditions were 63.8 °C for 35 min. The assay amplified only I. hauseri, with no cross-reaction with the related species Pityogenes spessivtsevi, Ips typographus, Ips subelongatus, and Hylurgus ligniperda; its limit of detection was 100 pg of genomic DNA; and it amplified efficiently from adults, larvae, pupae, and a single egg. Positive results could be scored directly by eye from the red-to-yellow colour change in the reaction, requiring no precision instruments at any step. Using a non-destructive alkaline crude-DNA extraction (HotSHOT), the assay also amplified I. hauseri directly from single adults and larvae, confirming its compatibility with a rapid, field-simple sample preparation. The LAMP assay was rapid, specific within the tested panel, and simple. However, broader validation with additional sympatric non-target species and geographically distinct populations of I. hauseri is needed before routine field or quarantine application.

Insects doi: 10.3390/insects17080837

Authors: Emre Evlice Mustafa Alkan Ömer Cem Karakoç Sait Ertürk Reyhan Bahtiyarca Yasemin Yücel Yücel Ali Rıza Tüfekçi Ümit Yırtıcı

Investigating alternatives to synthetic chemicals in pest management is essential. The bioactivity of Artemisia absinthium and A. dracunculus essential oils (EOs) was evaluated against two stored-product insect pests (Sitophilus granaries and Tribolium castaneum) and two root-knot nematodes (Meloidogyne incognita and M. chitwoodi). EOs were hydrodistilled and analyzed by GC-MS: A. absinthium consisted mainly of myrtenyl acetate (47.10%) and β-thujone (11.41%); A. dracunculus of methyleugenol (26.02%), β-asarone (14.04%), and elemicin (10.95%). In contact bioassays, A. absinthium caused 93.2–96.8% mortality against S. granarius, but minimal effect on T. castaneum. A. dracunculus caused 66.3–73.5% mortality against S. granarius, no effect on T. castaneum, yet reduced progeny by 87%. Both EOs strongly repelled T. castaneum but weakly affected S. granarius. A. dracunculus exhibited 100% nematicidal efficacy against M. incognita and 94.9% against M. chitwoodi; A. absinthium showed limited effect. A. dracunculus showed minimal hatching inhibition (<30%), whereas A. absinthium increased hatching. Sparse Partial Least Squares (sPLS) prioritized pulegone, methyleugenol, β-asarone, β-thujone, myrtenyl acetate, and β-phellandrene as constituents co-varying with AChE/BChE responses, with docking identifying pulegone as the top ligand. These findings demonstrate species-specific bioactivity patterns: A. dracunculus shows strong nematicidal and reproductive inhibitory effects, whereas A. absinthium shows potent acute toxicity and repellency against S. granarius, supporting multi-target biopesticide strategies to mitigate risks of synthetic chemical treatments.

Insects doi: 10.3390/insects17080836

Authors: Dongliang Su Weifang Yang Yanan Fan Xiuxia Li Yun Huang

Spodoptera frugiperda (J.E. Smith) is a notoriously destructive and invasive agricultural pest, causing substantial economic losses worldwide. Research has shown that cytochrome P450s play an important role in detoxifying insecticides. However, the precise molecular mechanism of P450-mediated detoxification of pyrethroids in S. frugiperda remains largely unknown. Enzyme activity assays demonstrated the involvement of P450 monooxygenases in pyrethroid detoxification in S. frugiperda. Subsequently, the results of induction experiments revealed that CYP9A58 and CYP9A59 were significantly upregulated by bifenthrin (up to 4.59- and 5.54-fold) and lambda-cyhalothrin (up to 4.17- and 3.28-fold). Stage- and tissue-specific expression analyses suggested that CYP9A59 exhibited predominant expression in sixth-instar larvae, and CYP9A58 was primarily expressed in the moth stage, with both P450 genes showing high transcript levels in the midgut. The functional role of P450s was confirmed by RNAi, where knockdown of either CYP9A58 or CYP9A59 significantly increased larval susceptibility to lambda-cyhalothrin, raising mortality by 45.71% and 57.68%, respectively. Furthermore, structural modeling demonstrated the capacity of both P450 enzymes—CYP9A58 and CYP9A59—to form stable complexes with pyrethroid insecticides. Collectively, these results confirm that CYP9A58 and CYP9A59 are key mediators of pyrethroid detoxification, conferring insecticide tolerance in S. frugiperda.

Insects doi: 10.3390/insects17080835

Authors: Jerzy A. Lis Paweł J. Domagała Barbara Lis Anna Zielińska

Previous molecular and morphological analyses have suggested that the family Parastrachiidae and the subfamily Sehirinae of the family Cydnidae may be more closely related than previously thought. However, no conclusive study has yet been conducted to support their recognition as a monophyletic group within the superfamily Pentatomoidea. Our analyses identified a strongly supported clade comprising species of the subfamily Sehirinae and the family Parastrachiidae. Based on the results of the present study, together with previous research on mitochondrial and nuclear DNA sequences, secondary and tertiary structures of 18S rRNA, and morphological characters, the subfamily Sehirinae is elevated to family status (Sehiridae stat. nov.), with two subfamilies (Sehirinae and Parastrachiinae). Furthermore, the subfamily Sehirinae is divided into two well-defined monophyletic tribes, Sehirini and Ochetostethini, and the subfamily Parastrachiinae is divided into Parastrachiini and Dismegistini trib. nov.

Insects doi: 10.3390/insects17080834

Authors: Bo Li Jing Ni Zhenguo Yang Yonghong Zhang Lingli Li Limin Huang Xingrong Bai Yang Hu

Eocanthecona furcellata Wolff, a predatory stinkbug, has garnered much attention as a biological control against Lepidoptera, Coleoptera, and Hemiptera pests across various crops. The continuous and high-quality supply of prey is essential for its large scale rearing and commercialization. This study investigated the life history and population performance of E. furcellata fed on Lepidoptera prey, Bombyx mori larvae or on Coleoptera prey, Tenebrio molitor larvae under controlled conditions. Using age-stage two-sex life table methodology, we evaluated key developmental parameters and population growth potentials of E. furcellata fed on two types of prey. Results revealed significant differences in pre-adult duration (19.06 vs. 20.47 days), survival rate (0.98 vs. 0.89), adult longevity (27.50 vs. 15.77 days), total pre-oviposition period (25.17 vs. 26.74 days), oviposition days (8.17 vs. 5.37 days), and fecundity (445.54 vs. 222.38 eggs/female) between B. mori vs. T. molitor-fed population. Population features between B. mori vs. T. molitor-fed populations, such as the intrinsic rate of increase (0.17 vs. 0.15 d−1), finite rate of increase (1.1906 vs. 1.1628 d−1), net reproductive rate (218.56 vs. 100.69 ± 22.45 offspring/female), and generation time (3.97 vs. 4.59 days), also diverged markedly. Collectively, B. mori larvae were a much better prey than T. molitor larvae to rear E. furcellata.

Insects doi: 10.3390/insects17080833

Authors: Xueqing Li Xuanda Chen Zhen Gong Yu Peng

Arachnids evade predation by intentionally sacrificing body parts, with leg autotomy playing a crucial role in their survival and reproductive strategies. Our study primarily employed field surveys and laboratory experiments to examine the frequency of autotomy and its effects on predation and mating in Ebrechtella tricuspidata (Araneae: Thomisidae). Leg loss was common in wild populations, with approximately 17.11% of all surveyed spiders missing at least leg, the most frequently lost leg is one of the second pair of appendages, and the highest rate of autotomy occurs in July. Additionally, we found that some individuals exhibit regenerative capacity following autotomy. We focused on the effects of leg autotomy on E. tricuspidata in two contexts: predation and mating. In laboratory conditions, the loss of two legs significantly impacted the individual’s predatory efficiency. Additionally, individuals missing two legs exhibited significantly poorer mating performance than intact individuals. We suggest that E. tricuspidata may employ a synergistic strategy of “autotomy-regeneration” to mitigate survival risks, thereby reducing the negative impacts of leg loss on predation and mating.

Insects doi: 10.3390/insects17080832

Authors: Maria Luigia Vommaro Anita Giglio

Early adult life represents a critical developmental window during which insects undergo profound physiological reorganization. Despite the economic importance of the yellow mealworm, Tenebrio molitor L., this transition remains poorly characterized/understood. This study provides an integrated characterization of the energetic, cuticular and immunological remodelling that occurs during the first week post-emergence, a critical developmental window with important implications for experimental standardization and mass-rearing optimization. Body mass, Scaled Mass Index (SMI), and cuticular tanning trajectories were monitored at 0, 1, 5, and 7 days, along with cellular (tsotal haemocyte count, THC) and humoral (phenoloxidase activity, PO) immunocompetence at 2 and 7 days in both sexes. Newly emerged adults underwent an energetically demanding early phase characterized by significant proportional mass loss, followed by stabilization and improved SMI by day 7. In parallel, THC increased more than twofold, while the humoral defences remained stable. Cuticle melanization followed a synchronized age-dependent trajectory in both sexes, reaching structural stabilization by the end of the first week. Correlation analysis revealed sex-specific patterns of resource allocation. Females showed a positive association between initial body condition and mature PO activity. Conversely, males exhibited a negative trend between cuticle tanning effort and PO activity, suggesting a clear competition for shared physiological resources. Overall, our findings identify early adulthood as a phase of coordinated physiological remodelling, during which energetic reorganization, cuticle maturation, and cellular immune expansion are synchronized to establish adult functional competence.

Insects doi: 10.3390/insects17080831

Authors: Cebrail Barut İnanç Özgen Halil Bolu Bilal Alataş Hakan Yildirim Ali Murat Tatar

The coloring process in cherry fruit affects both fruit quality and the cherry fly (Rhagoletis cerasi). This is critically important for host preferences of major pests such as cherry fly. In this study, a randomized classification method was used to classify five distinct coloration stages of cherry fruit based on pomological characteristics and cherry fly density data. An explainable hybrid model combining Random Forest (RF) and Ant Colony Optimization (ACO) algorithms has been developed. In this study, fruit samples of the Ziraat 900 variety were collected from four different cherry orchards in Elazığ province during five different coloration stages. Pomological characteristics such as weight, width, length, height, stem length, firmness, seed weight, soluble solids content (SSC), NaOH, and acidity were determined, and adult cherry fly densities were also recorded. In the proposed method, candidate decision rules generated by the RF algorithm were optimized using the ACO algorithm, and the most distinctive rule sets were selected. The results showed that the proposed RF-ACO model achieved a 99.48% accuracy rate and exhibited higher performance than many common machine learning methods. Feature significance analysis revealed that SSC, cherry fly density, NaOH, and acidity were the most effective parameters in the classification process. The model not only provided high accuracy thanks to the explainable IF-THEN rules it generated, but also allowed for expert interpretation of the decision-making process. The findings offer significant contributions to the development of decision support systems for determining cherry ripening periods and controlling the cherry fruit fly.

Insects doi: 10.3390/insects17080830

Authors: Wen-Ning Zhang Ke Li Shu-Lin Yao Jia-Yong Zhang Yue Ma

Mantidae exhibits the most extensive adaptive radiation within the order Mantodea; however, studies elucidating their internal phylogenetic relationships and spatio-temporal diversification patterns remain scarce. This study aims to resolve the long-standing taxonomic uncertainties within Mantidae by testing the hypothesis that the polyphyletic nature of several subfamilies—specifically Tenoderinae and Hierodulinae—is linked to an incomplete understanding of their mitochondrial genomic evolution. To address this, we assembled 16 complete Mantodea mitochondrial genomes, including seven representatives of the tribe Archimantini (Mantidae: Hierodulinae). Of these, 10 mitogenomes conform to the ancestral insect mitochondrial gene order proposed by Cameron and colleagues, but six mitochondrial gene orders do not conform to the ancestral insect mitochondrial gene order. We identified typical mantodean mitochondrial rearrangement patterns in three species, characterized by gene duplications within the trnA-trnR-trnN-trnS-trnE-trnF and CR-trnI-trnQ-trnM-trnM-ND2 gene cluster. Phylogenetic analyses corroborate the monophyly of Orthoderinae, Mantinae, Choeradodinae, Vatinae, and Archimantini within Mantidae; conversely, Tenoderinae and Hierodulinae are resolved as polyphyletic assemblages. Divergence time estimation indicates that the split between extant Mantodea and Blattodea occurred during the Middle Permian (275.4 Ma, 95% HPD: 207.07–329.09 Ma). Mantidae originated during the Late Cretaceous (87.83 Ma, 95% HPD: 58.89–118.23 Ma), with the diversification of most subfamilies of Mantidae occurring during the Late Cretaceous (80.48 Ma; 95% HPD: 54.86–106.41 Ma). Historical biogeographic analysis and the estimated divergence times suggests that the common ancestor of Mantidae originated within Gondwana during the Late Cretaceous. Ancestral range reconstructions identify Australasia realms and Neotropical realms as the most probable center of origination for Mantidae and achieved a global distribution by expanding along the trans-Antarctic route and leveraging the ‘Indian Ark’ effect.

Insects doi: 10.3390/insects17080829

Authors: Edwin Rodolfo Escobar-Olarte Gustavo Adolfo Rincón María Fernanda Vidal Ruth Mariela Castillo Agustín Góngora Sandra Carolina Montaño-Contreras María Carolina Velásquez-Martínez Jonny Edward Duque

Electroantennography (EAG) is a valuable approach for monitoring insect antennal responses to insecticidal and test compounds and may provide a preliminary screening method for identifying compounds with potential activity against medically important insect vectors. The objective of this study was to evaluate the EAG responses of Rhodnius prolixus to different xenobiotics and to compare these electrophysiological responses with host approach and protection against biting. Antennae from adult triatomines subjected to prolonged fasting (≥30 days) were exposed to the tested compounds. In parallel, live-bait behavioral bioassays were conducted using Gallus gallus and a newly designed laboratory device. Exposure to IR3535 and carvone produced a greater than 60% reduction in ammonia-induced EAG amplitude, consistent with the protection times observed in the behavioral assays (135.6 ± 43.29 min and 108.0 ± 26.33 min, respectively). These findings indicate that IR3535 and carvone alter antennal responses to ammonia and provide prolonged protection against R. prolixus bites. Because neither compound significantly delayed host approach, the observed behavioral effect was more consistent with biting deterrence than with demonstrated spatial repellency. EAG may therefore serve as a preliminary complementary screening approach, although its ability to identify compounds that interfere with hematophagous feeding requires further validation using larger and chemically diverse compound libraries.

Insects doi: 10.3390/insects17080828

Authors: Jie Wang Cheng-Xing Wang Yan Li Nicolas Desneux Su Wang Bin Tang

Cadmium (Cd) is a pervasive heavy metal pollutant in agricultural ecosystems, posing toxic threats to crop productivity, food safety, and the efficacy of biological control programs. The Asian corn borer (ACB), Ostrinia furnacalis is a destructive lepidopteran pest of maize in East Asia, while Trichogramma ostriniae serves as the most widely applied egg parasitoid for the sustainable management of this pest in integrated pest management (IPM) programs. However, the cascading effects of sublethal Cd stress transmitted from herbivorous hosts to egg parasitoids remain poorly understood. Here, we investigated the sublethal effects of dietary Cd exposure (5.0 mg/kg) on the development and Cd bioaccumulation of ACB, and subsequently evaluated the parasitism performance of the egg parasitoid T. ostriniae reared on Cd-contaminated host eggs. Results showed that chronic Cd exposure did not significantly affect larval weight, male pupal weight, or female pupal weight of ACB, but significantly increased female adult body weight, indicating stage-specific stimulatory effects. Cd concentrations in larvae, female pupae, and female adults of ACB were markedly elevated following dietary exposure, with the highest Cd loads detected in female pupae (41.23 mg/kg). However, maternal Cd transfer to eggs did not result in a statistically significant increase in egg Cd concentration. Notably, parasitism by T. ostriniae on Cd-contaminated ACB eggs significantly increased the number of eggs parasitized, although offspring emergence rate and female progeny ratio remained unaffected. This study fills the research gap regarding the trophic transfer of Cd between ACB and T. ostriniae, clarifies the complex bottom-up effects of Cd pollution on host–parasitoid interactions, and provides empirical references for the rational deployment of T. ostriniae as a biocontrol agent in Cd-contaminated maize fields.

Insects doi: 10.3390/insects17080827

Authors: Ya-Wen Chang Ling Zhong Zhen Yuan Yu-Zhou Du

Liriomyza trifolii is a global pest of vegetables and ornamental plants and a major invasive species in China. Long-term irrational use of chemical insecticides has reduced control efficacy, driving interest in plant-derived alternatives. Bitter gourd, Momordica charantia, extracts show potential against various pests, but their effects on L. trifolii are unknown. To address this, host suitability tests were first conducted and revealed that L. trifolii exhibited significantly higher adaptability to kidney bean than to bitter gourd in terms of both oviposition and feeding, and failed to complete its life cycle on bitter gourd. Further treatment with ethanol extracts of bitter gourd leaves demonstrated dose-dependent adulticidal activity; at the LC50 concentration, the extract not only reduced feeding punctures and oviposition, but also significantly decreased egg hatching and larval survival, while showing no significant impact on pupation or emergence. To elucidate the underlying molecular mechanisms, integrative transcriptomic and metabolomic analyses were subsequently performed. Transcriptomics identified 254 differentially expressed genes (DEGs) enriched in ribosome, oxidative phosphorylation, and peroxisome pathways, and upregulated DEGs included a vitellin-degrading protease and cytochrome P450. Meanwhile, metabolomics detected 272 differential metabolites (DEMs): upregulated metabolites were linked to purine metabolism, while downregulated ones were associated with cysteine/methionine and arginine/proline metabolism. Integrated analysis revealed “Biosynthesis of amino acids” as the sole common pathway, with S-adenosyl-L-homocysteine, N-succinyl-LL-2,6-diaminoheptanedioate, and glutamine synthetase (Ltr05G008090) showing significant correlations. These findings suggest that reprogramming of amino acid and nitrogen metabolism may participate in the response and could serve as a candidate response pathway. Accordingly, this study may offer a theoretical basis for the future development of botanical insecticides based on bitter gourd leaf extract against L. trifolii.

Insects doi: 10.3390/insects17080826

Authors: Yingying Wang Ruijun Liu Guoquan Wang Keda Chen Weihai Li

The stonefly genus Sinacroneuria Yang and Yang, 1995 (Plecoptera: Perlidae) is restricted to East Asia and represents an important component of freshwater biodiversity. However, the taxonomy of Chinese Sinacroneuria has not been comprehensively revised, resulting in difficulties in species identification. In this study, we conducted a systematic review of the Chinese species based on morphological characters. Before the present study, Sinacroneuria comprised 20 described species worldwide, 18 of which were recorded from China. The five new species bring these totals to 25 species worldwide and 23 in China, representing increases of 25 percent and 27.8 percent, respectively. All Chinese species are diagnosed, and five new species, S. dayaoshan sp. nov., S. fengyanghu sp. nov., S. magnimaculata sp. nov., S. similiwui sp. nov., and S. yunjishan sp. nov., are described. An updated identification key to all Chinese species is also provided. These results improve our understanding of the diversity and taxonomy of Sinacroneuria and provide an important taxonomic reference for future biodiversity, ecological, and biomonitoring studies.

Insects doi: 10.3390/insects17080825

Authors: Zanandra Z. Tamiosso Daniela N. Godoy Ramon B. Palharini Jéssica L. S. Grzybowski Marylia P. Cargnin Venicius E. Pretto Arthur Dallanora Josemar Foresti Dionei S. Muraro Paulo R. da Silva Oderlei Bernardi

Spodoptera frugiperda (Lepidoptera: Noctuidae) is a key insect pest of maize in Brazil. However, the evolution of insecticide resistance has raised concerns about the risk of control failures under field conditions. This study assessed insecticide efficacy and estimated the risk of control failure in Brazilian populations of S. frugiperda exposed to selected insecticides. Nine field populations were collected from representative maize-producing regions of Brazil during the 2024/2025 and 2025/2026 seasons. Early third-instar (L3) larvae from these populations were exposed to the highest label rate of ten insecticides representing different modes of action in maize leaf bioassays. Mortality was assessed 96 h after exposure, and the risk of control failure was based on the efficacy threshold of 80% mortality. Significant effects of population, insecticide, and the population × insecticide interaction were detected, indicating variation in susceptibility among the sampled populations. Methoxyfenozide + spinetoram, spinosad, chlorfenapyr, and spinetoram consistently caused high mortality (>81%) and were associated with low risk of control failure across all populations. In contrast, chlorantraniliprole exhibited reduced efficacy with mortality below the expected efficacy threshold in most populations and a high risk of control failure. Population-dependent variation in insecticide efficacy was also evident for metaflumizone, emamectin benzoate, thiodicarb, indoxacarb, and methoxyfenozide, with corresponding variation in the risk of control failure. These findings show that insecticide efficacy and the risk of control failure depend on the specific insecticide–population combination and provide valuable information to support decision-making regarding insecticide selection and the rotation of modes of action within insect resistance management (IRM) and integrated pest management (IPM) programs.

Insects doi: 10.3390/insects17080824

Authors: Marina Hakim Minmin Xu Diying Huang

Abundant new material of protopsyllidiids was collected from the late Middle Jurassic Yangshuzhuang Formation at Jiyuan City, Henan Province, Central China, and is described herein. The dominant form was assigned to the species “Poljanka hirsuta Yang, Yao & Ren, 2012”, first described from the Daohugou beds (Haifanggou Formation, Inner Mongolia, North China). Furthermore, the species is herein transferred from the genus Poljanka Klimaszewski, 1995 to Cicadellopsis Martynov, 1937 and renamed Cicadellopsis hirsuta (Yang, Yao & Ren, 2012) comb. nov. based on the presence of a forked vein RA in the forewings, as evidenced by the newly discovered specimens. A second protopsyllidiid species, Poljanka jiyuanensis sp. nov., is also described and illustrated, showcasing the diversity of Protopsyllidioidea in the Mesozoic Chinese deposits. Abundant specimens of Cicadellopsis hirsutacomb. nov. have been discovered in both the Yangshuzhuang Formation at Jiyuan, Henan Province, and the Haifanggou Formation at Ningcheng, Inner Mongolia, further supporting their biostratigraphic correlation. This also indicates that the early assemblage of the Yanliao biota, represented by the Daohugou biota, was distributed at least as far south as Central China.

Insects doi: 10.3390/insects17080823

Authors: Nassima Meghazi Abdel Madjid Benzehra Abdenour Boumechhour Aissam Bousbia Rudy Megido Caparros Frédéric Francis Slimane Boukraa

Mosquitoes are significant public health insects responsible for numerous vector-borne diseases. Injudicious chemical use has developed metabolic and genetic resistance in mosquitoes. This study evaluated the repellent efficacy of five essential oils (EOs) from local plants [Mentha spicata I, Ruta tuberculata, Mentha spicata II, Lavandula latifolia, and L. stoechas]. M. spicata I and R. tuberculata EOs were extracted using Clavenger hydrodistillation. Simultaneously, the remaining EOs were obtained through a local extraction distillation unit. Chemical composition was identified using GC-MS. Repellency was assessed using the arm-in-cage method, by rearing Culex pipiens s.l. and Aedes albopictus in the laboratory. Additionally, mixtures containing 15% DEET, 15% IR3535, 5% vanillin, and 10% M. spicata I EO were tested. Both mosquito species were clearly repelled by all EOs. M. spicata I was most potent at 10% concentration. The complete protection time (CPT) at 10% M. spicata I EO was increased using blended mixtures containing 15% DEET, 15% IR35353, or 5% vanillin. Regional variations in M. spicata EOs were detected. This study may serve as a foundation for cosmetic manufacturers and pest control products. Developing botanical and hybrid (natural and synthetic) formulations could provide strong protection against insect bites, particularly from disease-vector mosquitoes, helping to prevent vector-borne diseases.

Insects doi: 10.3390/insects17080822

Authors: Min Dai Chiyu Hu Hong Miao

Early pest infestations can significantly reduce chili pepper yield and quality. Therefore, timely and accurate pest detection is essential for precision pest management. However, pest detection under practical cultivation conditions remains challenging because of small target sizes, dense distributions, partial occlusion, and complex background interference. To address these challenges, this study proposes HCFD-YOLOv8, a task-oriented lightweight visual detection framework based on YOLOv8n for pepper pest monitoring in complex agricultural environments. A novel Cross-Stage Partial Hybrid Spatial Attention (CSP-HSA) module is developed as the core feature enhancement component. It is designed to improve fine-grained pest feature extraction while reducing computational redundancy. CSP-HSA combines cross-stage partial feature reuse, heterogeneous convolution, lightweight spatial-channel attention, and channel shuffle to enhance discriminative representations of small and densely distributed pests. In addition, a Cross-Scale Context Fusion Module (CCFM) is introduced to improve information interaction between high-resolution spatial details and high-level semantic features across different scales. DyHead and Inner-MPDIoU are further incorporated as complementary components to enhance adaptive feature perception and bounding-box localization, especially for partially occluded and overlapping targets. Experimental results show that YOLOv8n achieves a Precision of 84.0% and an mAP50 of 87.1%, whereas HCFD-YOLOv8 improves these values to 90.9% and 92.0%, respectively, corresponding to increases of 6.9 and 4.9 percentage points. Meanwhile, the proposed framework reduces the number of parameters, model weight-file size, and FLOPs from 3.00 M to 2.43 M, from 5.97 MB to 4.96 MB, and from 7.5 G to 6.5 G, respectively. The model achieves an inference throughput of 39.40 FPS on the evaluated cloud-server platform. Comprehensive ablation experiments demonstrate that DyHead delivers the largest standalone improvement in detection accuracy, whereas CSP-HSA provides a more favorable trade-off between feature enhancement and computational efficiency. CCFM and Inner-MPDIoU further provide complementary improvements in cross-scale feature representation and bounding-box localization. These results indicate that HCFD-YOLOv8 achieves a favorable balance between detection accuracy and computational efficiency, demonstrating its potential for lightweight and accurate pepper pest monitoring under complex agricultural conditions.

Insects doi: 10.3390/insects17080821

Authors: Liqiang Liang Linyan Tian Shanxin Gao Shengli Wu Bo Wei Yulu Yi Nanni Ma Jingwei Luo Jingwen Sheng Shangning Yang Shaohan Tang Songkun Su Hongyi Nie

In insects, tyrosine hydroxylase (TH) plays crucial roles in a wide variety of biological processes. However, its function in Apis mellifera remains unknown. Here, AmTH (A. mellifera TH) was cloned and characterized. Expression profiles at different stages showed that AmTH was highly expressed in 2-day-old eggs and during the pupal stage. Tissue expression profiles of newly emerged workers revealed that AmTH was highest expressed in the wings, followed by the legs and antennae. To explore the function of AmTH, gene-edited worker larvae were generated using CRISPR/Cas9 technology, and the edited individuals died at the larval and prepupal stages. In addition, a TH inhibitor (3-IT) was administered via larval feeding and the survival rates were significantly lower in groups fed with 800 μM, 3200 μM, and 12,800 μM of 3-IT in a dose-dependent manner. To investigate the role of AmTH in honeybee immunity, 8-day-old worker bees were fed with 3-IT and subsequently injected with lipopolysaccharide. The results showed that the mRNA expression of Relish, antimicrobial peptide-related genes, TH and DDC were significantly downregulated, whereas laccase 2 and yellow-y were significantly upregulated. These findings indicate that AmTH is indispensable for larval development and adult immunity in honeybees.

Insects doi: 10.3390/insects17080820

Authors: Maria K. Sakka Eirini Karanastasi Reggina Krassi Marianna Rigopoulou Ioannis P. Markou Georgia Baliota Paraskevi Agrafioti Christos G. Athanassiou Christos I. Rumbos

The present study evaluated the insecticidal efficacy of a commercial formulation containing azamethiphos (Teenox® EC) against adults of the saw-toothed grain beetle, Oryzaephilus surinamensis, the lesser grain borer, Rhyzopertha dominica (F.), and the granary weevil, Sitophilus granarius (L.), under laboratory conditions. The azamethiphos formulation was assessed both as grain treatment on wheat and barley at 0, 2.5, 5, 10 and 20 ppm for all species, and as surface treatment on concrete and plastic surfaces at 0, 0.125, 0.25, 0.5 and 1 μg a.i./cm2 for O. surinamensis and R. dominica. In grain treatments, adult mortality increased significantly with concentration and exposure interval for all species. Mortality was generally higher in barley than in wheat, particularly after longer exposure periods. Sitophilus granarius was the most susceptible species, reaching high mortality at the highest concentration, whereas R. dominica exhibited lower mortality responses, especially at lower concentration. Progeny production was significantly reduced with increasing concentration for all species, although the effect was more pronounced in barley than in wheat, particularly for O. surinamensis. In surface treatments, mortality was strongly influenced by surface type, with significantly higher efficacy on concrete compared to plastic. Mortality increased with both concentrations and exposure time for all species, while interspecific differences were less pronounced than in grain treatments. These responses indicate that both substrate characteristics and exposure time are important parameters of azamethiphos efficacy. Overall, the results indicate that the azamethiphos formulation tested can provide effective control of key stored-product beetle species when applied either on grains or different surfaces, although its performance is influenced by commodity and surface type. These findings highlight the potential of azamethiphos as a versatile tool in integrated stored-product pest management programs.

Insects doi: 10.3390/insects17080819

Authors: Xianheng Ouyang Hongbo Duan Zhikuan Cao Yuntian Liu Fanrui Ge Peng Nie Shihao Wang Tayyab Shaheen Qiaoyun Sun

Climate change may redistribute forest pests, pathogens, natural enemies, and host trees, yet these components are still often projected independently. We used ensemble species distribution models (SDMs) to map potential climatic suitability for Monochamus alternatus, Dastarcus helophoroides, Scleroderma guani, Bursaphelenchus xylophilus, and a genus-level Pinus host layer, and then summarized niche overlap, range overlap, and multispecies co-suitability under SSP1-2.6, SSP3-7.0, and SSP5-8.5 for the 2050s and 2090s. A structural equation model (SEM) fitted to thresholded binary layers was retained only as an exploratory description of conditional spatial associations. Because its inputs were suitability classifications rather than abundance, infection, parasitism, nematode load, or transmission data, neither arrow direction nor coefficient sign is interpreted causally. The strongest joint modeled suitability for the vector, pathogen, host, and at least one natural enemy occurred in East Asia, whereas B. xylophilus alone also showed potential climatic suitability in parts of the Americas and Africa. Importantly, the current model underpredicted the established occurrence of B. xylophilus in Portugal and western Spain, demonstrating that mapped unsuitable cells cannot be interpreted as confirmed absence. The genus-level Pinus layer similarly represents broad host availability rather than species-specific susceptibility. Because the future maps are based on averages across three general circulation models and the archived outputs do not permit retrospective estimation of inter-model variability, these projections should be treated as screening-level, scenario-conditioned summaries rather than uncertainty-bounded forecasts. The results identify priorities for surveillance and field validation, but they do not quantify disease incidence, interaction strength, or biological-control efficacy.

Insects doi: 10.3390/insects17080818

Authors: Fernando Moya Tamara Segovia-Jara Valeria Tapia Catalina Aguilar Jordan Hernandez-Martelo Laura M. Pérez Manuel J. Suazo Alexis Matheu Yostin Añino Dumas Gálvez Emilio Romero-Romero Alonso Santos Carmen Rodríguez-Poveda Hugo A. Benítez

Habitat loss and deforestation are among the main drivers of biodiversity decline in tropical ecosystems, yet their effects on developmental stability remain poorly understood in many insect groups. Orchid bees (Apidae: Euglossini) have been proposed as potential bioindicators of environmental quality due to their close association with forested habitats and sensitivity to habitat disturbance. Here, we evaluated the relationship between forest cover, wing morphology, and developmental stability in the orchid bee Euglossa imperialis across five protected areas of Panama exhibiting different levels of deforestation. A total of 290 individuals were analyzed using geometric morphometrics and fluctuating asymmetry (FA) of the forewing. Morphological variation was assessed through Principal Component and Canonical Variate Analyses, whereas developmental instability was quantified using Procrustes ANOVA and FA scores. Wing shape showed moderate differentiation among sites, with La Tronosa, the most deforested protected area, exhibiting the greatest morphological divergence. In contrast, FA displayed a clear association with habitat degradation. La Tronosa presented the highest levels of developmental instability, and generalized linear models revealed a significant positive relationship between deforestation and FA at both local and landscape scales, with landscape-level deforestation showing the strongest effect. Our results indicate that developmental instability is more sensitive than overall wing morphology for detecting the biological consequences of habitat alteration. These findings support the use of fluctuating asymmetry as an early indicator of environmental degradation and provide new evidence for the value of orchid bees as bioindicators in tropical ecosystems.

Insects doi: 10.3390/insects17080817

Authors: Jie Zhang Guanfeng Xu

Steroid hormones govern diverse physiological processes during juvenile-to-adult development across vertebrates and invertebrates, ranging from pubertal initiation in mammals to metamorphosis in insects. Ecdysteroids, the collective name for many moulting hormones in insects, act as master effectors driving metamorphic development. Their biosynthesis begins with dietary cholesterol as the direct precursor (phytosterols are converted as needed) and is driven by a series of enzymatic reactions catalyzed by the evolutionarily conserved Halloween genes to produce ecdysone, which is ultimately converted into its potent metabolite 20-hydroxyecdysone (20E) in target tissues to induce extensive morphological and physiological changes. The precise temporal pattern of molting and metamorphosis is dictated by periodic ecdysone surges originating from the prothoracic gland. Given the extensive utility of Drosophila as a major model organism for investigating systemic growth and developmental timing, this review synthesizes recent insights into the regulatory mechanisms underlying ecdysone biosynthesis. In this review, we begin by outlining the ecdysteroid biosynthetic cascade and core catalytic enzymes in the prothoracic gland, followed by a systematic discussion of diverse regulatory strata, encompassing substrate availability, transcriptional regulation and chromatin accessibility, and their vital contributions to the control of ecdysteroid production.

Insects doi: 10.3390/insects17080816

Authors: Muhammad Z. Ahmed Justin George

The two-spot cotton leafhopper (Amrasca biguttula) is an emerging invasive pest in the southeastern United States, with recent establishment in cotton, vegetables, and ornamental hibiscus. Its rapid spread, potential economic losses, and regulatory impacts highlight the need for additional early-warning tools capable of identifying high-risk arthropod invaders before widespread establishment. We developed and applied the Normalized Research Risk Metric (NRRM), a literature-based framework that quantifies global research visibility using total publications, recent research, research momentum, and geographical breadth. A comprehensive multi-database Web of Science search was conducted across all available indices using species-specific synonyms, address filters, and harmonized country names. Six globally important invasive species were used to train the model, and A. biguttula was evaluated as the primary prediction species. The species exhibited high global research visibility (T = 403; C = 25) and a positive NRRM score (0.651), consistent with its long-recognized pest status in Asia and its rapid emergence in the U.S. In contrast, Heliococcus summervillei received a strongly negative NRRM score (−1.14). NRRM provides a rigorous early-warning indicator that can be integrated with ecological and eco-climatic models to further improve the prediction of future invasive threats in agricultural and horticultural systems.

Insects doi: 10.3390/insects17080815

Authors: Yaonian Chen Xuefeng Jiang Dening Wang Qing Dong Xiaona Zhang Yifeng Wang Wenbing Ye

The facultative endosymbiont Serratia symbiotica significantly influences the ecological fitness of its aphid host. However, the molecular mechanisms by which Serratia affects the host’s symbiotic organ, the bacteriocyte, remain poorly understood. Here, we conducted a comparative transcriptomic analysis of bacteriocytes from Serratia− and Serratia+ pea aphid (Acyrthosiphon pisum) strains. Our analysis revealed that Serratia colonization extensively modulates gene expression within bacteriocytes. Key metabolic pathways were significantly altered: genes involved in ribosomal biogenesis and oxidative phosphorylation were upregulated, while those in fatty acid biosynthesis were downregulated. Furthermore, we observed a complex reshaping of the immune profile, characterized by a broad downregulation of immune recognition and signaling components alongside an upregulation of specific effector genes and antioxidant enzymes. These findings suggest that Serratia induces a state of enhanced anabolic capacity and energy production in bacteriocytes, coupled with strategic reallocation of resources and a finely tuned immune response that balances symbiont tolerance with control. Our RT-qPCR validation confirmed the RNA-seq results, further supporting these results. This study provides the first bacteriocyte-specific transcriptomic resource for the aphid–Serratia interaction system, offering novel insights into the molecular integration of a facultative symbiont into host physiology.

Insects doi: 10.3390/insects17080814

Authors: Tong-Yin Xie Yan Zhang Yi-Zhu Chen Zheng Liu Xiao-Long Lin

Species delimitation and biodiversity assessment in Chironomidae are frequently hindered by morphological conservatism and widespread cryptic diversity. Neozavrelia (Diptera: Chironomidae), a genus inhabiting specialized freshwater microhabitats such as springs and hygropetric seepages, remains poorly understood with respect to its genetic diversity and the environmental processes underlying lineage differentiation. Clarifying lineage diversity is a prerequisite for evaluating the ecological factors associated with genetic differentiation. In this study, we compiled a global COI DNA barcode dataset comprising 137 sequences from newly generated specimens and publicly available records in the Barcode of Life Data Systems (BOLD). Genetic diversity was evaluated using neighbor-joining (NJ) analysis and Automatic Barcode Gap Discovery (ABGD), whereas environmental and geographic drivers of genetic differentiation were assessed using Mantel tests, distance-based redundancy analysis (db-RDA), variation partitioning, and hierarchical partitioning. A total of 26 molecular operational taxonomic units (MOTUs) were identified, with most lineages forming well-supported clades in the NJ tree. Genetic differentiation was significantly associated with both environmental and geographic distances, although environmental variables explained a substantially greater proportion of the observed variation. Hierarchical partitioning identified slope, annual cloud cover, mean precipitation amount of the coldest quarter, and frost frequency as the principal environmental predictors of lineage differentiation. Our findings reveal substantial COI genetic diversity within Neozavrelia and suggest that environmental heterogeneity, particularly variation in water availability and thermal conditions, is significantly associated with lineage differentiation. This study expands the global COI DNA barcode reference library for Neozavrelia and provides new insights into ecological and evolutionary factors associated with diversification in freshwater chironomids.

Insects doi: 10.3390/insects17080813

Authors: Shengxiang Zhang Yating Liu Wenhui Song Chunjiu Ren Junwen Ai Bing Han Huiju Gao Bing Wang

In the published publication [...]

Insects doi: 10.3390/insects17080812

Authors: Khavhatondwi Rinah Mofokeng

Insects are fundamental to ecosystem functioning and human welfare, yet their multifaceted contributions to ecological services, food security, rural livelihoods, and cultural heritage remain insufficiently represented in mainstream scientific research and policy. Despite growing global recognition of insect decline and the potential of entomophagy to address food system challenges, integrated evidence linking global ecological knowledge with community-level indigenous practices is lacking, particularly in sub-Saharan African contexts. A narrative bibliometric review was conducted through systematic searches of Web of Science, Scopus, and PubMed databases, supplemented by FAO, IPBES, and MDPI Insects repositories. Searches were conducted between January 2024 and May 2026 using keyword combinations spanning entomophagy, ecosystem services, insect decline, indigenous knowledge and edible insects in Africa. Four thematic dimensions are synthesised: (1) ecological services, (2) nutritional value and food security, (3) economic contribution and livelihoods, and (4) socio-cultural and ethnomedicinal significance. The Venda region of Limpopo Province emerges as a compelling case study of how insect–human relationships intersect with biodiversity conservation, food security, and rural development. Actions include integrating indigenous knowledge with scientific research, strengthening sustainable community-based insect harvesting practices, and incorporating edible insects into South Africa’s food, nutrition, and biodiversity policies in alignment with global sustainability and biodiversity goals.

Insects doi: 10.3390/insects17080811

Authors: Rasheed Akbar Sadia Manzoor Irfana Lalarukh Gul Makai Somia Shehzadi Asif Ali Khan Ning Di Jianfan Sun Asmat Ullah Jibiao Fan

The melon fruit fly, Bactrocera zonata, and the pumpkin fruit fly, Bactrocera cucurbitae (Diptera: Tephritidae), are important agricultural pests that cause significant losses in a wide range of fruit and vegetable crops. Increasing concerns over pesticide resistance and environmental contamination have driven interest in plant-derived insecticide alternatives. This study investigated the insecticidal activity of Ricinus communis L. leaf extracts against both species. The crude leaf extract was fractionated using solvents of increasing polarity (n-hexane, methanol, and ethyl acetate). The resulting fractions were assessed for insecticidal activity, and the most active fraction was further purified using column chromatography. Chemical constituents were identified using gas chromatography–mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FTIR). Bioassay results indicated that the methanol, n-hexane, and ethyl acetate fractions exhibited the highest insecticidal activity against both B. zonata and B. cucurbitae. GC-MS analysis revealed several bioactive constituents in the active fractions, including neophytadiene, fatty acid derivatives, and 11,14,17-eicosatrienoic acid, which was tentatively identified as a candidate constituent associated with the most active fractions. These findings suggest that R. communis leaf extracts contain bioactive constituents with insecticidal properties against tephritid fruit flies and may contribute to the development of plant-based pest management strategies. However, further work is required to isolate pure compounds and confirm their individual toxicological roles under field conditions.

Insects doi: 10.3390/insects17080810

Authors: Yanan Luo Sha Hua Longzheng Wang Shanchun Yan Qi Wang

Tomicus pilifer is an important wood-boring forest pest in China, and its host localization and intraspecific communication rely on the perception of volatile chemical cues. However, the molecular mechanisms underlying odor recognition in this species remain largely unknown. In this study, we systematically investigated the behaviorally active volatiles present in the hindgut and feces of T. pilifer and elucidated the roles of odorant-binding proteins (OBPs) in their recognition. Gas chromatography–mass spectrometry (GC–MS) identified eight volatile compounds common to both hindgut and fecal samples. Among them, five terpenoid compounds, α-pinene, 3-carene, D-limonene, camphene, and β-myrcene, elicited significant electroantennogram (EAG) responses and induced positive behavioral attraction in adults. Based on antennal transcriptome data, phylogenetic relationships with functionally characterized homologous OBPs, preliminary molecular docking analyses, and tissue-specific expression patterns, three candidate OBPs (TpilOBP5, TpilOBP16, and TpilOBP29) were selected from 51 identified TpilOBP genes and subsequently expressed as recombinant proteins. Fluorescence competitive binding assays demonstrated that all three OBPs bound to the five behaviorally active terpenoid volatiles, with TpilOBP29 exhibiting the broadest ligand-binding spectrum and the highest binding affinity. Molecular docking and interaction analyses further revealed that the binding pocket of TpilOBP29 forms a continuous hydrophobic core composed of multiple conserved hydrophobic residues, which cooperatively stabilizes ligand binding through hydrophobic interactions, π–alkyl interactions, and van der Waals forces, thereby conferring broad-spectrum and high-efficiency odorant recognition. These findings provide new insights into the molecular mechanisms underlying the recognition of key behaviorally active terpenoid volatiles in T. pilifer, identify TpilOBP29 as a key mediator of odor recognition, and provide a potential molecular target for the development of environmentally friendly semiochemical-based behavioral management strategies against bark beetle pests.

Insects doi: 10.3390/insects17080809

Authors: Fida Hussain Magsi Amees Ullah Yihui Ma Jianrong Huang Guoping Li Xincheng Zhao Hongqiang Feng

Artificial light at night (ALAN) and the broader use of artificial light in agriculture are increasingly recognized to affect the physiology and behavior of nocturnal insects, yet their influence on pheromone-mediated reproductive communication in economically important insect pest species remains poorly understood. Here, we investigated the effects of artificial illumination on calling behavior, sex pheromone production, blend composition, and mating success in the fall armyworm Spodoptera frugiperda, under both laboratory and semi-field conditions. Virgin females were exposed during the scotophase to one of four wavelength-specific treatments, including dark control, red (620 nm), green (520 nm), or blue (460 nm) LED light. Female calling behavior occurred during the early-to-mid scotophase under dark and red light conditions, while it was significantly delayed and suppressed under blue and green light. Specifically, blue light suppressed production of the key pheromone component (Z)-9-tetradecenyl acetate (Z9-14:Ac) and enhanced (Z)-11-hexadecenyl acetate (Z11-16:Ac), altering the species-specific pheromone blend composition. Mating success was significantly reduced under blue light in both laboratory and semi-field experiments. Under controlled laboratory conditions, green light also affected mating success, but this effect was not significant in the semi-field experiment. Blue light imposed the strongest inhibitory effect, reducing mating success by 39% relative to the dark condition. Red light produced minimal effects in all measured parameters, consistent with reduced sensitivity to longer wavelengths in nocturnal moths. These results demonstrate that wavelength-specific artificial light can disrupt several components of the reproductive communication system in S. frugiperda and suggest that manipulation of artificial light may offer a non-chemical approach for disrupting mating behavior in economically important insect pest species within integrated pest management programs.

Insects doi: 10.3390/insects17080808

Authors: Shakil Ahmad Dasong Chen Yongjie Cen Momana Jamil Hina Gul Valeria Palma-Onetto Gecheng Ouyang Meng Xiang

Food security faces significant challenges due to the growing threat of insect pests and global climate change, making it essential to adopt sustainable agricultural strategies. Plants possess intrinsic defense systems that are activated in response to herbivore attack, including the emission of specialized volatile organic compounds (VOC) known as herbivore-induced plant volatiles (HIPVs). These volatiles aid the foraging of natural enemies (predators and parasitoids), thereby contributing to biological control of pest populations. Harnessing these chemical defense mechanisms offers a promising avenue for pest management, although natural enemy attraction does not necessarily result in pest suppression or increased crop yield. This review synthesizes plant and insect-derived chemical signaling mechanisms with direct relevance to biological control in crop agroecosystems, including field crops, orchards, vegetable systems, and protected cultivation. We emphasize recent applied research while retaining selected foundational studies that established the principal concepts and mechanisms underlying chemically mediated pest management. Considering the importance of chemical signaling in sustainable agriculture, we propose four key research directions: (1) optimizing plant defense induction mechanisms; (2) integrating HIPVs with natural enemy pheromone-based attractants; (3) combining habitat management with the provision of plant-derived food resources; and (4) harnessing plant defenses through breeding and infochemical-based genetically modified crops. Additionally, we examine the potential impacts of environmental stressors on plant–herbivore chemical communication, underscoring their importance for resilient and environmentally sustainable agricultural systems.

Insects doi: 10.3390/insects17080807

Authors: Ali Bilgin Yılmaz Milad Afşar Muhammed Yasul Mahsa Torkamanian Afshar Adnan Ayan Özge Oktay Ayan Yaşar Göz Loğman Aslan

Ectoparasites cause skin lesions, anemia, and mortality in wild animals and act as vectors of zoonotic pathogens. This study reports ectoparasites detected during an opportunistic survey on wild mammals admitted to the Van Yuzuncu Yil University Wildlife Protection and Rehabilitation Center in eastern Türkiye during 2024–2025. Due to the opportunistic nature of sampling, the findings primarily reflect parasite burdens in injured or debilitated individuals and may not be representative of healthy free-ranging populations. Of the 28 animals examined, 20 (71.4%) were infested. A total of 449 ectoparasites were collected: 370 fleas (82.4%), 58 ticks (12.9%), and 21 lice (4.7%). Identified species included four fleas (Paraceras melis, Chaetopsylla globiceps, Pulex irritans, Archaeopsylla erinacei), four ticks (Ixodes kaiseri, Rhipicephalus turanicus, Haemaphysalis parva, Haemaphysalis erinacei), and one louse (Trichodectes melis). This study provides new host–ectoparasite association records for Türkiye: I. kaiseri and R. turanicus on beech marten (Martes foina); I. kaiseri and C. globiceps on Eurasian badger (Meles meles); and P. irritans on Eurasian lynx (Lynx lynx) and brown bear (Ursus arctos). Bipartite network analysis revealed moderate specialization (H2’ = 0.52) and marked variation in host specificity, with T. melis, A. erinacei, and P. melis showing high host specificity (d’ > 0.85), whereas Chaetopsylla globiceps and Pulex irritans acted as generalists (d’ < 0.30). Some identified ectoparasites are known or suspected vectors of zoonotic pathogens. These findings provide baseline data for future research on wildlife health and disease transmission risks in the region.

Insects doi: 10.3390/insects17080806

Authors: Jiachen Huang Zikai Han Wangpeng Shi

Megalurothrips usitatus (Thysanoptera: Thripidae) is a key destructive pest of cowpea, resulting in considerable economic losses. Understanding M. usitatus’s oviposition preference in various plant parts under distinct photoperiod treatments is important for its success in pest control. We placed mated females with cowpea stems, leaves and pods in rearing boxes. After 24 h, eggs were counted after basic fuchsin staining. Hatched nymphs were recorded over 7 days. Morphology and histology were examined by microscopy and scanning electron microscopy. A statistical comparison on the number of egg-laying and hatching nymphs was conducted in different cowpea parts under photoperiod (L:D = 18:6) and continuous darkness (L:D = 0:24). Under photoperiod (L:D = 18:6), oviposition preference ranked as follows: pods (61.7%) > leaves (29.4%) > stems (8.9%). Nymph numbers followed the same order (79.5%, 14.9%, and 5.5%, respectively). Eggs were laid beneath leaf epidermis, concentrated around leaf veins. Under continuous darkness, total nymphs (284) did not differ from photoperiod (L:D = 18:6) (308). The numbers of stem and pod-hatched nymphs were decreased, while the leaf-hatched nymphs increased significantly (46 to 106). In conclusion, M. usitatus prefers pods for oviposition. Darkness does not alter total reproductive output but increases oviposition and hatch rate in leaves, shifting egg spatial distribution among plant parts.

Insects doi: 10.3390/insects17080803

Authors: Mureed Abbas Yiyan Zhao Abdul Basit Jianqin Zhang Xuemei Qin Yunhe Fan

Rab proteins are key members of the Ras superfamily that regulate vesicular trafficking in eukaryotic cells, ensuring accurate cargo transport and cellular homeostasis. To investigate the functional role of Rab proteins, RNA interference (RNAi) was employed to silence LmRab11A in Locusta migratoria, followed by integrated transcriptomic and metabolomic analyses. Transcriptomic profiling identified 54 downregulated and 71 upregulated genes upon LmRab11A knockdown. Based on Log2 fold change values and statistical significance, 15 downregulated genes were selected for further analysis. RT-qPCR validation confirmed that 9 of these genes were significantly downregulated following LmRab11A silencing. Subsequent RNAi-mediated knockdown of these 9 genes revealed that silencing of only LOCMI11062 (β-tubulin) resulted in 100% mortality and severe morphological defects in locust nymphs, indicating its critical role in development. Metabolomic analysis identified 11 significantly altered metabolites, including 8 exhibiting increased abundance and 3 exhibiting decreased abundance. Spearman correlation analysis between the 9 downregulated genes and the altered metabolites suggested potential associations between 6 metabolites and specific genes. Collectively, these findings demonstrate that suppression of LmRab11A disrupts downstream gene expression and alters the metabolite network, thereby impairing growth and development.

Insects doi: 10.3390/insects17080805

Authors: Pasquale Ciliberti Sigitas Podėnas Virginjia Podėnienė Jekaterina Havelka

The family Limoniidae is the most species-rich within the order Diptera. The classification of this family is still unresolved and is based largely on morphological studies and the opinions of a few specialists. The rapid advancement of molecular techniques has created new opportunities to address long-standing systematic challenges. Nevertheless, relatively few studies have used molecular data to refine our understanding of Limoniidae and its relationships with allied lineages. In the present study, we reviewed publications that applied molecular approaches to improve the classification of Limoniidae and clarify its relationships with related groups. Relevant studies were identified through the literature section of the Catalogue of the Craneflies of the World using the keywords “classification”, “systematics”, and “molecular”. We retained only studies that employed molecular data to investigate the classification of Limoniidae, the phylogenetic position of the family within Tipuloidea, and the placement of Tipulomorpha within the dipteran tree. The studies reviewed consistently support the conclusion that Limoniidae is not monophyletic. In contrast, Tipulomorpha is consistently recovered as a monophyletic lineage, although its position within the dipteran tree remains controversial. Consequently, a satisfactory taxonomic framework has yet to be achieved. Recent advances in high-throughput sequencing and the generation of large-scale molecular datasets provide unprecedented opportunities to resolve these systematic uncertainties. We therefore advocate expanding both taxon sampling and the number of genetic markers included in phylogenetic analyses. Ultimately, a coordinated effort among research groups and institutions is likely to represent the most effective strategy for resolving the taxonomy and evolutionary relationships of Limoniidae.

Insects doi: 10.3390/insects17080804

Authors: Baishu Li Sihan Jin Haomiao Li Rui Li Li Li Junzheng Zhang Tao Liu

Bactrocera dorsalis (Diptera: Tephritidae) ranks among the most serious quarantine pests threatening global fruit and crop production. Irradiation has been adopted worldwide as an eco-friendly phytosanitary treatment strategy, yet how B. dorsalis responds to irradiation is not fully understood. To investigate the transcriptional response to irradiation, third-instar B. dorsalis larvae were exposed to two X-ray doses: a sub-effective dose of 15 Gy and a phytosanitary dose of 120 Gy. Comparative transcriptomic profiling revealed a clear dose-dependent escalation in the number of differentially expressed gene (DEGs). While 15 Gy primarily disrupted basic metabolism and cuticle integrity, 120 Gy induced a systemic metabolic collapse coupled with severe genotoxic stress, activating DNA repair, lysosomal degradation, and the JAK-STAT signaling pathway. Notably, we identified nine dose-specific candidate biomarker genes that are exclusively regulated at the phytosanitary dose. These findings elucidate the molecular network mediating radiation-induced mortality and provide rapid molecular diagnostic tools for validating phytosanitary irradiation efficacy and optimizing pest management strategies.

Insects doi: 10.3390/insects17080802

Authors: Jinghao Ji Yanjun Xu Yang Li Hongxing Xu Zhongxian Lu Ronggen Wen Sunan Shen Yan Wu Jianlei Huang Jiawen Guo

Loxostege sticticalis is a destructive pest that survives winter by entering diapause. Photoperiod and temperature trigger this dormancy, but their effects on gut bacteria are unclear. We hypothesized that photoperiod and temperature interact to alter the gut bacterial community structure and function and that these microbial changes may be involved in diapause preparation. To test this hypothesis, this study investigated how different photoperiod (L10:D14 and L16:D8) and temperature (18, 22, 26 and 30 °C) combinations shape the gut bacterial communities and their predicted functions in L. sticticalis larvae using 16S rRNA sequencing. The larval gut contained 29 phyla, 52 classes, 128 orders, 205 families, 407 genera, and 281 ASVs at species-level taxonomic annotation. Under a short-day photoperiod (L10:D14), the 26 °C treatment caused a dramatic loss of α-diversity and an almost complete dominance of Enterococcus (99.96%). β-diversity clearly separated this group from all others. LEfSe identified Enterococcus as its exclusive biomarker. Functionally, this group showed significantly elevated carbohydrate metabolism but reduced amino acid metabolism, energy metabolism, and metabolism of cofactors and vitamins. No such simplification occurred under long-day photoperiod (L16:D8) or at other temperatures under short-day conditions. These findings raise the hypothesis that gut microbiota may participate in metabolic reprogramming during diapause preparation and that environmental factors such as photoperiod and temperature could mediate host life history strategies via the microbiota. However, because diapause status was not directly measured, this connection remains an inference. If validated, these microbial changes could provide a basis for developing novel pest management strategies by targeting the processes associated with diapause induction.

Insects doi: 10.3390/insects17080801

Authors: Constantin S. Filintas Nickolas G. Kavallieratos Maria C. Boukouvala

Tribolium confusum is a destructive global pest of processed grains, causing severe economic damages in storages. After the application of synthetic insecticides to surfaces, they degrade, allowing insects to come in contact with lower concentrations of the toxicant. This study focused on the investigation of the sublethal impacts of the pyrrole insecticide chlorfenapyr across different surface types (plastic, glass, metal, cement) on T. confusum. Using Toxtrac for automated video tracking, we quantified locomotor traits of T. confusum adult males and females. Chlorfenapyr surface treatment at LC10 and LC30 suppressed the locomotor activity of T. confusum adults. Important mobility traits were quantified using ToxTrac analysis, such as average speed, average acceleration, total distance, exploration rate, mobility average speed, and total time frozen. In the untreated groups, beetles displayed high levels of activity, with average speeds exceeding 50 mm/s on glass, plastic, and cement. After insecticide exposure, all locomotor traits declined across all surface types, except for total time frozen, that showed a positive correlation with the increase in concentration of chlorfenapyr. Treatments on non-porous materials (plastic, glass, metal) caused higher mobility suppression in both sexes in comparison to respective treatments on cement. These effects were more prevalent at LC30 vs. LC10. Chlorfenapyr induced a strong, negative effect on the mobility behavior of T. confusum adults across all tested surfaces, highlighting the value of automated behavioral tracking for detecting and quantifying key mobility impairment on specific traits relevant to stored-product pest management.

Insects doi: 10.3390/insects17080800

Authors: Gisele Ivonne Antonuccio Pablo Julián López Marcelo Facundo Berretta Diego Herman Sauka

Microbial communities associated with insect larvae play key roles in host nutrition, protection against pathogens, immune modulation, and represent a source of biotechnologically relevant traits. In Alphitobius diaperinus, a major poultry pest, the gut microbiota has been mainly studied at the community level, providing limited insight into the potential roles of individual microorganisms. Here, we characterized the aerobically culturable fraction of the larval gut microbiota derived from a single pooled homogenate of fifteen larvae under stable laboratory rearing conditions—an approach that uniquely enables strain-level genomic resolution, functional experimentation, and biotechnological exploitation. Ten bacterial strains and two yeasts were initially isolated; eight bacterial isolates were identical, revealing the most frequently recovered cultivable bacterial morphotype. We provide high-quality draft genomes for five members of the A. diaperinus cultivable gut microbiota—Enterobacter hormaechei subsp. xiangfangensis strain INTA AN1-1, Staphylococcus hominis subsp. novobiosepticus strain INTA AC1-4, Staphylococcus succinus subsp. succinus strain INTA AC1-8, Hyphopichia burtonii strain INTA AB1-1, and Debaryomyces fabryi strain INTA AB1-4—establishing a genome-resolved reference framework validated through a polyphasic approach. Genome-scale annotation enabled us to predict the metabolic potential and hypothesize the functional capabilities among cultivable members, providing a foundation for future studies on this economically relevant pest.

Insects doi: 10.3390/insects17080799

Authors: Ana M. E. Camargo García Stephanie Samaniego Gustavo Quirós Pablo Montero-Prado

Organic waste valorisation using black soldier fly larvae (BSFL), Hermetia illucens L., offers a biological strategy to transform biodegradable residues into biomass with potential feed applications. This study evaluated five fruit–vegetable residue mixtures under tropical conditions: 100% fruit (100F), 100% vegetables (100V), 50% fruit–50% vegetables (50F–50V), 70% fruit–30% vegetables (70F–30V) and 30% fruit–70% vegetables (30F–70V), using three independent rearing units per diet. The analysis included initial egg mass, estimated viable larvae, coffee husk input as structural bulking material, tray-level process conditions, larval biomass, dry feed offered and estimated bioconversion indicators. The 100F treatment produced the greatest dry biomass (0.1311 ± 0.0132 kg), while 100V and 50F–50V showed favourable input-normalised responses. Biomass was also expressed relative to estimated viable larvae and dry feed offered to support treatment interpretation under the operational conditions evaluated. Coffee husk improved substrate handling and was incorporated into the dry-matter balance; therefore, adjusted BCR was interpreted as a process balance indicator and complemented with biomass yield per dry feed offered. Estimated protein values ranged from 35.4% to 38.1% in selected composite samples. Salmonella spp. were absent in pooled microbiological samples, Escherichia coli was <10 CFU/g, and screened heavy metals were below the laboratory detection limit in selected composite samples. Overall, the results support the potential of BSFL systems for valorising local fruit and vegetable residues under tropical conditions.

Insects doi: 10.3390/insects17080798

Authors: An-Na Yang Yu-Xin Feng Ke Li Hang Li Su Wang Yuan-Xi Li

Objectively defining an effective choice is crucial for the reliability of results in insect olfactory behavior research. Relying on subjective time thresholds often leads to inconsistent findings, primarily due to the high likelihood of mistaking an accidental intrusion for an effective choice. Our analysis indicated that 29% of preference responses were not consistent among 0 s, 15 s, 30 s, and 60 s, when these thresholds were applied to evaluate the behavioral responses of Trichogramma japonicum Ashmead (Hym.: Trichogrammatidae) to 20 odorants in a four-arm olfactometer. This inconsistency arises because subjective thresholds fail to distinguish between accidental, transient entries and sustained, purposeful choices, leading to false positives or false negatives. To address this issue, we compiled a database of the initial stay duration of T. japonicum in the odor zone, and applied the 5th percentile of its empirical distribution—a widely accepted statistical standard for excluding extreme outliers (i.e., accidental brief entries) in medical and biological research—as the threshold to differentiate between accidental intrusion and effective choice. We then systematically assessed the behavioral responses of T. japonicum to 20 odorants and validated the authenticity of olfactory preferences through oviposition choice experiments. A continuous stay of ≥10 s was determined as an effective choice. Based on this criterion, T. japonicum exhibited significant preference for 0.1 μg/μL α-pinene, 0.01 μg/μL D-limonene and 0.001 μg/μL citral, whereas avoiding 10 μg/μL β-ionone. The results of the oviposition choice experiments showed high consistency with the olfactory behavioral preferences, confirming the reliability of this standard in predicting its actual host selection decisions. Collectively, this study proposes a data-driven protocol for establishing an objective and stable behavioral criterion in insect olfactory behavior research.

Insects doi: 10.3390/insects17080797

Authors: Zhaoyun Lyu Hongyan Song Yue Zhang Qitong Huang Meng Sun

The mason bee Osmia excavata Alfken (Hymenoptera: Megachilidae) is an essential pollinator for rosaceous fruit trees in northern China, but its populations are declining because of severe infestations by the mite Chaetodactylus hirashimai Kurosa (Acari: Sarcoptiformes). This mite feeds on pollen within mason bee nest tubes, thereby impairing larval development. However, the effects of different floral resources on the fitness of C. hirashimai remain unclear. Herein, we evaluated the development, survival, and reproduction of C. hirashimai reared on four diets (cherry pollen, cherry bee bread, apple pollen, or apple bee bread), by using an age-stage, two-sex life table. Chaetodactylus hirashimai successfully completed its life cycle on all diets. Cherry pollen supported shorter pre-adult development, longer adult longevity, and higher fecundity than apple pollen. Bee bread diets resulted in significantly lower pre-adult mortality (11.76–14.81%), and higher fecundity (270–278 eggs/female) and net reproductive rate (R0 = 115–120 offspring/individual), than raw pollen (44.64–44.83% mortality; 117–179 eggs/female; R0 = 40–50 offspring/individual). No significant differences in the intrinsic rate of increase (r) and finite rate of increase (λ) were observed among diets. Our findings demonstrated that cherry pollen is a highly favorable resource for C. hirashimai, and bee bread further enhances mite population growth. This study highlights the ecological conflict between cherry pollination and mite infestation, and these life-table results can provide preliminary laboratory support for subsequent research on integrated mite control in fruit orchards.

Insects doi: 10.3390/insects17080796

Authors: Wei Yin Vinnie-Siow Tiong Kai Tan Sing Sin Sam Yvonne Ai-Lian Lim Boon Teong Teoh Van Lun Low

The chikungunya virus (CHIKV) is an emerging alphavirus transmitted primarily by Aedes mosquitoes. This narrative review synthesised evidence from 56 mosquito-based records (34 field surveillance records and 22 laboratory vector competence records) published from January 2020 to June 2026. Aedes aegypti was the most frequently detected species, confirmed as CHIKV-positive in 22 of the 29 field studies that examined it, followed by Aedes albopictus (positive in nine of 12). Both species demonstrated consistent laboratory competence. Descriptive laboratory analysis showed mean infection, dissemination, and transmission values of approximately 76%, 77%, and 37% for Ae. aegypti, and 79%, 80%, and 47% for Ae. albopictus, respectively; these values are descriptive summaries across heterogeneous laboratory protocols and inconsistently reported genotypes. East/Central/South African–Indian Ocean Lineage of the chikungunya virus (ECSA-IOL) showed the highest mean transmission efficiency among genotype groups. In addition, CHIKV RNA was also detected in Culex quinquefasciatus, Psorophora spp., Wyeomyia spp., and other culicids in field studies, but laboratory evidence does not support these species as confirmed competent vectors. Other Aedes species, including Aedes vittatus, Aedes polynesiensis, Aedes koreicus, and Aedes japonicus, may have regional relevance but require further validation. Key evidence gaps include incomplete genotype reporting, limited virus isolation from positive mosquito pools, and inconsistent transmission metrics. Future preparedness for CHIKV emergence and spread requires integrated surveillance combining field detection, virus isolation, genomic sequencing, and standardised vector competence assays within an integrated surveillance framework.

Insects doi: 10.3390/insects17080795

Authors: Assel A. Karabayeva Bakyt K. Kopzhasarov Gulnar K. Ziyaeva Nazira M. Duzbayeva Rabiga M. Kudaibergenova

Fruit mites, particularly Panonychus ulmi, Tetranychus urticae, and eriophyid mites, are among the most economically important arthropod pests in apple orchards, causing significant reductions in photosynthetic efficiency, fruit quality, and yield. Their management has traditionally relied on chemical acaricides; however, the widespread development of resistance, adverse effects on beneficial arthropods, and increasing environmental concerns have highlighted the limitations of pesticide-dependent control strategies. This review critically evaluates current advances in the management of major fruit mite species affecting apple orchards, with particular emphasis on Panonychus ulmi, Tetranychus urticae, and eriophyid mites. The biology, ecology, and economic significance of these pests are examined together with contemporary chemical control strategies, mechanisms of acaricide resistance, and sustainable resistance management. Particular attention is given to predatory mites, conservation biological control, habitat management, and ecological engineering as essential components of Integrated Pest Management (IPM). The review also examines the integration of biological, chemical, and cultural control measures within IPM programs and provides a regional perspective on fruit mite management in Southeastern Kazakhstan, highlighting local challenges, knowledge gaps, and opportunities for implementing ecologically based IPM systems. Emerging approaches, including precision agriculture, digital monitoring, molecular diagnostics, and climate-adaptive pest management, are also assessed. The available evidence indicates that sustainable fruit mite management requires a transition from pesticide-centered control toward integrated, ecologically resilient orchard protection systems in which biological control and IPM serve as the foundation, while chemical control functions as a targeted supporting tool. To our knowledge, no previous review has comprehensively integrated biological control, acaricide resistance management, ecologically based IPM, and region-specific challenges for fruit mite management in Southeastern Kazakhstan into a unified framework while also identifying key research priorities for Central Asia, including resistance surveillance, biodiversity conservation, climate adaptation, and digital decision-support technologies.

Insects doi: 10.3390/insects17080794

Authors: Bruno Matheus Gomes André Rodrigues de Souza Fábio Santos do Nascimento Carlos E. Sarmiento

Male and female paper wasps (Vespidae: Polistinae) perform different behavioral roles. Thus, sexes may experience distinct selective pressures that may ultimately affect body size, shape, and proportions. We investigated this in the neotropical Polistes simillimus. We compared 100 males and 100 females using linear morphometrics, geometric morphometrics, and allometric analyses of head, mesosoma, forewing, and fore femur. Females were larger than males in all linear measurements. After correcting for body size, males exhibited wider heads, longer mesosomas, and longer fore femora, whereas females had longer heads. Positive allometry of mesosoma length was detected in males and negative allometry of fore femur length in females. Geometric morphometrics confirmed differences in both forewing (rounder in males, elongated in females) and mesosoma (stouter in males). These findings are consistent with the contrasting behavioral demands experienced by each sex; they also generate testable hypotheses regarding the evolution of flight performance in these insects.

Insects doi: 10.3390/insects17080793

Authors: Diego Parrondo Monton Damiana Ravasi Nikoleta Anicic Mariantonietta Lettieri Pietro Storelli Arianna Puggioli Nisia Trisconi Matteo Tanadini Eleonora Flacio

The sterile insect technique (SIT) is considered a promising and environmentally sustainable tool for controlling Aedes albopictus. While current guidelines address its implementation in moderately large and partially isolated areas, evidence from small, fully urban and spatially connected environments remains limited. In 2025, we evaluated SIT in two municipalities in southern Switzerland, releasing sterile males in small (≈12 ha), non-isolated urban areas representing contrasting operational contexts within ongoing integrated vector management programs. Entomological responses were assessed using a spatial, distance-based framework integrating ovitrap-derived egg abundance and hatching rates from treated and surrounding zones, alongside adult female monitoring. Following releases, egg abundance declined within treated areas relative to surrounding zones, with model-based peak reductions of approximately 57% in Ascona and 67% in Losone. Egg hatching rates were also lower within treated areas, with estimated reductions of approximately 9% and 22%, respectively. For both indicators, spatial analyses revealed gradual distance-dependent patterns rather than abrupt boundary effects. No consistent pattern was detected for adult female abundance, likely reflecting limited sampling intensity. The spatial and temporal responses observed across the two study sites suggest that SIT may contribute to modifying local reproductive dynamics of Ae. albopictus even in small, non-isolated urban areas under operational conditions.

Insects doi: 10.3390/insects17080792

Authors: Julia J. Vieira Casey L. Johnson Elizabeth M. Varkonyi Howard S. Ginsberg Steven R. Alm

The main objectives of this study were to look at bee visitation to some common forage plants that could be used in place of or in conjunction with turfgrasses and to compare establishment methods to increase pollinator forage in turfed landscapes. Bee foraging patterns were assessed on four flower species: white clover (Trifolium repens L.), medium and mammoth red clover (Trifolium pratense L.), crimson clover (Trifolium incarnatum L.), and common selfheal (Prunella vulgaris L. var lanceolata [Barton] Fern.) by conducting quadrat surveys on two floral plots in southern Rhode Island. Flower species were planted in randomized replicated plots to assess comparative foraging patterns of local bee species. Medium Trifolium pratense had the highest number and diversity of bee foragers in 2022. In 2023, T. pratense maintained high visitation, but the trend in diversity of visitors shifted, with T. repens and P. vulgaris having the highest bee species richness. Floral visitation generally followed shifting floral abundances, with some variation among bee species, potentially due to selective preferences. Overall, Trifolium spp. and P. vulgaris are valuable floral resources that support a wide range of bee species and can be included in pollinator plantings, incorporated into mowed turf areas/lawns, or used separately to enhance available bee forage. We also present results on the effectiveness of five different methods (flail mowing, flail mowing/slice seeding, rototilling, herbicide, and occultation via weed fabric) in establishing these four species as well as creeping thyme (Thymus serpyllum L.) in turf.

Insects doi: 10.3390/insects17080790

Authors: Elena Romero Antonia Soto

The invasive mealybug Delottococcus aberiae (De Lotto) has become a major citrus pest in eastern Spain during the last decade. The parasitoid Anagyrus aberiae (Guerrieri) is currently used in a classical biological control program against this pest, although important aspects of the interaction between both species remain poorly understood. We evaluated host-stage suitability and the effects of parasitism on host reproduction, as well as demographic performance and parasitoid response to host density under laboratory conditions. The parasitoid successfully parasitized D. aberiae stages from second-instar nymphs to adults, but preferred adult females, which accounted for 86% of parasitism when different stages were offered simultaneously. Parasitism reduced reproductive output by more than 93% in pre-reproductive females and caused oviposition cease within two days in females that had already initiated egg laying. Anagyrus aberiae exhibited an intrinsic rate of increase (rm) of 0.099, and a Type II functional response, reaching a maximum parasitism rate of 8.7 hosts per day. The strong suppression of host reproduction and favorable population growth parameters highlight the biological control potential of A. aberiae. These findings provide valuable information for optimizing mass-rearing protocols and release strategies, thereby improving the implementation of biological control programs against D. aberiae.

Insects doi: 10.3390/insects17080791

Authors: Xiao-Han Di Shuo Liu Duo Wang Jing-Ze Liu

Iron-sulfur clusters are a class of functionally diverse protein cofactors. In recent years, significant progress has been made in insect research on iron-sulfur clusters, revealing that they serve as a core molecular hub that integrate multiple physiological processes. This review systematically summarizes the structural characteristics and biosynthetic pathways of iron-sulfur clusters, with an emphasis on insect-specific features in the stability of iron-sulfur cluster assembly proteins, cluster transfer mechanisms, and functional differentiation of ferredoxins. On this basis, it further elucidates the central roles of insect iron-sulfur clusters in energy homeostasis, reproductive capacity, ecdysis, detoxification metabolism, and magnetoreception, and revealed the potential regulatory mechanisms of iron–sulfur proteins in the aforementioned physiological processes in insects, including the electron transport chain, the tricarboxylic acid cycle, the AMPK/TOR signaling axis, cell cycle regulation, and P450 enzyme activity. These findings provide important theoretical foundations and potential molecular targets for the development of environmentally friendly pest control strategies with low resistance risk.

Insects doi: 10.3390/insects17080789

Authors: Dolev Fabrikant Yanzhe Fu Leonidas-Romanos Davranoglou

The evolution of novel feeding structures played a major role in the diversification of Hemiptera. Here, we investigate the morphology and inferred function of a highly specialized labium in the extinct Cretaceous planthopper families Neazoniidae and Mimarachnidae. These insects possessed a feeding apparatus unparalleled among extant Hemiptera that is characterized by an extremely elongated labium with a densely corrugated apical segment formed by sinusoidal cuticular folds. Comparative analysis, aided by micro-computed tomography, indicates that the cuticular corrugations were a mechanical adaptation that increased the flexibility of the tubular feeding structure while resisting kinking and buckling. We propose that this morphology facilitated probing within deep bark fissures and other mechanically resistant plant tissues, potentially enabling access to the vascular bundles. Similar corrugated feeding structures convergently occur in several unrelated Cretaceous hemipterans as well as some long-proboscid Mecoptera, suggesting that extinct Mesozoic ecosystems supported feeding strategies absent in their modern relatives. Furthermore, we propose the synonymy of Mimarachnidae with Neazoniidae based on the shared possession of this specialized labium morphology, along with other morphological features, establishing the taxonomic connection between nymph and adult specimens. We also transfer the unplaced genus Spinonympha to the family Neazoniidae and describe a new species of the genus Cretodorus.

Insects doi: 10.3390/insects17080788

Authors: Babu Saddam Shahamat Jawad Mohammed Abul Monjur Khan Cong Wei

This study presents the first record of Dundubia annandalei Boulard in Bangladesh and assesses its potential range dynamics through MaxEnt modeling under current and future climate scenarios (under the 2041–2026, 2061–2080, and 2081–2100 time periods). A total of 63 specimens, collected from various locations during field surveys in February–March 2025, were identified based on morphological characteristics. The species distribution model exhibited excellent predictive performance (AUC = 0.967). Precipitation of the warmest quarter (64.4%), elevation (10.8%), and precipitation of the driest month (9.1%) were identified as the most influential environmental factors. Under current climatic conditions, the suitable area is predicted to cover 861,481 km2, representing 5.02% of the studied region. Future projections suggest range contraction (SSP585, 2041–2060) and expansion under all chosen emissions scenarios (SSP126 and SSP585), but significant expansion under extreme warming (SSP585), especially during 2061–2080 and 2081–2100. The potential distribution may extend to Bhutan, China, Myanmar, Laos, Nepal, Thailand, Vietnam, Malaysia, Indonesia, and the Philippines. Under climate change scenarios, the results highlight the potential for this species to emerge as a major agricultural concern in the future.

Insects doi: 10.3390/insects17080787

Authors: Ahmed M. M. Ahmed Verónica Andrade-Yucailla Eslam A. Y. Allam Mohammed A. A. Saad Samer H. Manaa Hassan F. Dahi M. S. Yones Freddy Alcocer-Quishpe Marcos Barros-Rodríguez

The Egyptian cotton leafworm Spodoptera littoralis (Boisduval) is a major polyphagous pest in vegetable and cotton crops. Accurate forecasting of its field generations is essential for effective integrated pest management (IPM). Forecasting its generations in the field is traditionally based on the trapping of males, but the use of temperature sums (degree-days, DD) could offer a robust alternative for triggering pest control interventions. The aim of this study was to monitor the flight activity and calculate the summations of degree-days, as well as to compare expected generation peaks and the reliability of S. littoralis males in predicting generations over three successive growing seasons. The study was carried out over three consecutive growing seasons (2017, 2018, and 2019) at Abnob district in Assiut Governorate, Egypt, comparing twice-weekly male captures using pheromone traps and emergence dates predicted by a degree-day model established from physiological data (development threshold: 10.5 °C; thermal constant: 480.6 DD for one generation). Laboratory experiments at four constant temperatures (17, 22, 27, and 32 °C) established the lower developmental thresholds and thermal constants for each life stage: egg (t0 = 11.86 °C; K = 40.10 DD), larva (t0 = 7.56 °C; K = 283.76 DD), pupa (t0 = 12.27 °C; K = 149.50 DD), and pre-oviposition period (t0 = 12.58 °C; K = 23.96 DD). Six successive generations (observed generations) appeared after the overwintering generation each year, with the overwintering generation consistently initiating in early May each season. The capture dates from the male sex-pheromone traps coincided with the adult emergence dates calculated by the accumulated heat model; deviations between observed (the occurrence of the real peak days) and predicted generation dates ranged from −2 to +2 days in the vast majority of cases, except for in the 2nd generation of the 2019 season, when the observed generation occurred 4 days before the expected generation date. Mean accumulated thermal units per generation ranged from 479.62 to 483.78 DD across the three seasons (grand mean: 481.95 DD), with overall mean seasonal deviations of 0.00, −0.14, and −0.43 days, confirming that the model predicts generation peaks to within ±2 days in the vast majority of cases. The integration of the two methods improves the reliability of phenological forecasting for S. littoralis, opens new opportunities for sustainable pest suppression, and improves the timing of control actions. This combined approach is recommended as a practical decision-support tool for IPM programs targeting S. littoralis in Egypt and comparable Mediterranean agroecosystems.

Insects doi: 10.3390/insects17080786

Authors: Shujuan Xu Ruirui Liu Qingxia Zhang Wenfan Zeng Shengrui Liang Guobin Lan Budan Duo Xi Li

Pollination services provided by insects are fundamental to the productivity and quality of sweet cherry orchards. This study investigated the flower-visiting insect community and compared the pollination potential of A. mellifera and A. cerana in a sweet cherry orchard on the Loess Plateau of eastern Gansu, China. Field surveys were conducted during the blooming periods of 2025 and 2026. Visual observation and video recording documented flower-visiting insects across five daily time intervals. Foraging behavior, including flower-handling time and inter-visit interval, was measured in both bee species. Pollen loads on five body parts (head, thorax, abdomen, wings, and legs) were measured by hemocytometry. Standing nectar volume was measured by capillary extraction. Statistical analyses included generalized linear models, Friedman tests, and Pearson correlation analysis. Fourteen insect taxa were identified, among which Hymenoptera was the most dominant order. The main visitors were A. mellifera and A. cerana. The peak of A. cerana visitation was at 12:00–14:00, whereas A. mellifera showed a broader activity peak spanning 12:00–16:00. Apis mellifera exhibited a significantly longer single-flower handling time compared to A. cerana, and inter-visit intervals did not differ significantly between species. Pollen loads showed both species carried the loosest pollen on their legs, but A. cerana also maintained a substantial load on its thorax. Pollen loads did not differ significantly between the two species on any body region. Pollinator activity and standing nectar volume both peaked at 14:00–16:00, but bee visitation showed no linear correlation with environmental factors. Although A. mellifera was numerically dominant, our findings indicate that A. cerana may play a disproportionate role in pollination because of its unique pollen-carrying profile and earlier peak of activity. Therefore, maintaining both honeybee species alongside a diverse assemblage of flower-visiting insects is a prudent strategy for resilient orchard pollination.

Insects doi: 10.3390/insects17080785

Authors: DongChan Im Daniel Dar Vincent Le Wenbo Li Dong-Hwan Choe

The Argentine ant, Linepithema humile (Mayr), is an important invasive pest in natural, agricultural, and urban ecosystems worldwide. Boric acid and thiamethoxam have been used as bait toxicants for Argentine ant management. Most of the toxicological investigations on these toxicants have focused on the mortality of the ants. However, their behavioral effects on target ants remain poorly understood. By focusing on the in-nest aggregation and out-nest activity level, the current study investigated the behavioral effects of low concentrations of boric acid and thiamethoxam on Argentine ants. Boric acid increased in-nest aggregation and reduced activity in the foraging area. In contrast, thiamethoxam treatment caused the ants to leave the nest and continue roaming in the foraging area. Individual behavior assay showed that overall mobility of ants was not impacted by any of the treatments, while thiamethoxam treatment caused ants to spend more time in the lighted area. Distinct behavioral impacts of these toxicants might be due to differences in their unique modes of actions. Understanding these behavioral effects of bait toxicants would help to optimize management protocols for the Argentine ant.

Insects doi: 10.3390/insects17080784

Authors: Doudou Li Qi Yao Jianjun Jiang Yang Yang Daifeng Cheng Ling Zeng Guangwen Liang Yongyue Lu

Chemical control is the main method used to manage the oriental fruit fly (Bactrocera dorsalis) in orchards. However, the oriental fruit fly has gradually developed resistance to multiple insecticides, posing significant challenges for pest resistance management. This study investigated changes in insecticide resistance in oriental fruit flies under different selection pressures. We identified resistance-related genes and their mutation sites using cDNA probes. Our results showed that resistance to trichlorfon decreased significantly in the absence of selection pressure. However, resistance increased when selection pressures were applied every 30 or 60 days. Although the resistance ratio showed a decreasing trend at every 90 and 120 days, a risk of a rebound remained. A large number of homologous sequences were identified in the suppression subtractive hybridization library of insecticide-resistant strains. Resistance to trichlorfon and alphamethrin primarily involves detoxification and metabolic genes, which are often associated with cross-resistance. A single gene may detoxify multiple pesticides, leading to cross-resistance. The four acetylcholinesterase mutations identified in this study are consistent with previous research findings. Moreover, resistance results from the combined action of multiple genes. Based on these findings, this study recommends avoiding continuous use of trichlorfon and maintaining an interval of more than 80 days between applications. It also emphasizes the importance of incorporating pesticide application intervals into integrated pest management strategies. This study provides a theoretical foundation for delaying resistance development in the oriental fruit fly, offers guidance on proper pesticide application intervals in the field, and contributes practical insights for pest resistance management.

Insects doi: 10.3390/insects17080781

Authors: Zhongjun Gong Jing Zhang Yun Duan Huiling Li Kebin Li Weizheng Li Yongsheng Yao Yuqing Wu Jin Miao

Two of the scarab beetle species examined here, Holotrichia oblita and Anomala corpulenta, show approximately 24 h intervals between locomotoractivity events; whereas, a third species, H. parallela, shows approximately 48 h intervals. We collected head tissues from all three species at a single time point, when the two 24 h rhythm species were activeand the 48 h rhythm species was not, and profiled their transcriptomes. Core clock genes showed comparable transcripts per million (TPM) valuesacross species at this time point. Expression differences were observed in genes involved in phototransduction (Gq alpha subunit isoforms) and mitochondrial energy metabolism (adenine nucleotide translocase isoforms). Additionally, 22 orthologs, including genes related to the ubiquitination cascade and 20S proteasome subunits, showed varying TPM values across species. Protein–protein interaction network analysis showed that many of these genes with varying TPM values cluster into conserved functional modules. This work is therefore presented solely as a descriptive transcriptome resource for these three beetle species at the collection time point.

Insects doi: 10.3390/insects17080783

Authors: Regina Gerstenbrand Zoltán Tóth Ferenc Samu Gergely Tholt

Plant-mediated interactions can modify herbivore behaviour and vector-borne plant disease dynamics, yet the systemic consequences of prior cereal leaf beetle (Oulema spp.) window-pane feeding for later phloem feeder vectors remain unclear. We hypothesised that prior Oulema window-pane feeding induces systemic changes in barley that alter the subsequent host acceptance and feeding behaviour of Psammotettix alienus. Plants received one of three 24 h treatments on one leaf: Oulema pre-colonisation, standardised artificial vascular injury or an undamaged control. Leafhopper responses were measured on a different, systemic leaf using female choice assays and electrical penetration graph recordings. Oulema damage was low and strongly right-skewed and did not affect most feeding variables, including non-phloem activities, phloem activity, drinking latency or phloem activity latency. Artificial vascular injury, however, reduced the phloem–saliva ratio in females, which indicates a lower relative investment in phloem preparation once the phloem phase was reached. Within Oulema-treated plants, increasing damage reduced the number of transitions between penetration phases in males but not females. Females showed no treatment-related preference in salivary sheath production or oviposition. Thus, Oulema window-pane feeding left only a weak systemic plant-mediated legacy for P. alienus, closer to behavioural neutrality than strong facilitation or interference under these short-term systemic experimental conditions.

Insects doi: 10.3390/insects17080782

Authors: Huifen Liu Huiju Gao Yu Xiu Lifeng Hua Lin Zhu Guang Guo Yaru Dong

Homologous regions (hrs) are repetitive DNA sequences widely distributed in baculovirus genomes, and are known to function as transcriptional enhancers. In this study, we systematically characterized the seven hrs (hr1, hr2L, hr2R, hr3, hr4L, hr4R, and hr5) from a novel isolate of Bombyx mori nucleopolyhedrovirus (strain BmNPV-YT). The seven hrs range from 390 to 880 bp in length and consist of 1–7 repeat units of approximately 72 bp, each containing a 30 bp palindrome with an EcoRI site. Structural diversity among the hrs includes variable numbers of stem–loop motifs, major late transcription factor (MLTF) sites, cAMP response elements (CRE-like), and 12-O-tetradecanoylphorbol 13-acetate (TPA)-response elements (TRE-like). Functional assays using luciferase reporter plasmids revealed that all seven hrs function as potent transcriptional enhancers for both homologous and heterologous promoters in vitro and in vivo. In BmN cells and fifth-instar silkworm larvae, the hrs enhanced the homologous ie1 promoter 11–1258-fold and 43–1545-fold, respectively, with hr2L showing the strongest activity (counts per minute: 4.82 × 108 in cells; 7.08 × 107 in larvae) and hr4R the weakest. Similarly, when driving the heterologous AcMNPV ie1 promoter in Sf21 cells and larvae, enhancement ranged from 19- to 1023-fold and 13- to 449-fold, respectively, again with hr2L and hr3 showing maximal effects and hr4R minimal enhancement. Notably, all the hrs, except hr4R, also stimulated the homologous late p10 promoter, with activation levels of up to 37.7-fold in vitro and 79.2-fold in vivo, significantly above baseline. However, hr4R showed negligible or no enhancement (0.84–1.05-fold). Among all the active hrs, hr5 emerged as the most potent enhancer of the p10 promoter. Spearman’s correlation analyses demonstrated that enhancer efficiency for all three promoters (homologous ie1, heterologous ie1, and homologous p10) correlated significantly with the number of palindromic sequences, the combined count of CRE and TRE motifs, and the total number of characteristic sequences (r = 0.873–0.982, p < 0.05 or p < 0.01). Collectively, our findings clarify the structural features of hrs from the newly isolated strain BmNPV-YT, systematically identify their promoter preferences and host adaptability as transcriptional enhancers, and establish their structure–function relationships. These findings provide novel insights into the transcriptional regulation of baculoviruses and offer valuable tools for optimizing baculovirus expression vector systems.

Insects doi: 10.3390/insects17080780

Authors: Hyunjee Kim Olga Frunze Sang Mi Han Soon Ok Woo Jewon Jung Hyung-Wook Kwon

Climate warming increasingly threatens honey bee health, yet diet-associated molecular patterns under thermal stress remain poorly understood. In this study, newly emerged honey bees were fed eight dietary treatments, including natural diets (honey and bee bread) and artificial diets (sugar syrup and pollen substitute diets), for 5 days before exposure to acute heat stress (45 °C for 4 h). Transcriptional responses were quantified by quantitative real-time PCR (qRT-PCR) using genes associated with nutrient sensing, metabolism, immunity, and stress responses, and the resulting expression profiles were analyzed using principal component analysis, hierarchical clustering, and univariate statistical analyses. Distinct diet-associated transcriptional patterns were observed under both baseline and heat-stress conditions. Under baseline conditions, transcriptional variation was primarily associated with nutrient-sensing and metabolic pathways, whereas under heat-stress conditions, metabolic and stress-response pathways contributed more strongly to transcriptional variation. Sugar syrup-fed honey bees exhibited elevated expression of several immune-related genes following heat stress, suggesting greater physiological disturbance. In contrast, honey- and bee bread-based diets exhibited more coordinated regulation of nutrient-sensing and metabolic pathways and comparatively lower expression of selected immune-related genes. These findings demonstrate that dietary quality is associated with distinct molecular profiles under thermal stress and provide mechanistic insights into the relationship between nutrition and gene expression under heat-stress conditions, supporting the development of nutrition-based strategies for promoting honey bee health under climate warming.

Insects doi: 10.3390/insects17080779

Authors: Yongbang Li Zhiqiang Hu Yating Guo Bingjie Du Jing Yu Yu Zhang Qianqian Du Guangwei Li Daowen Wang Di Wu

The sorghum aphid (Melanaphis sorghi), a phloem-feeding insect pest, causes severe economic losses in sorghum-producing regions worldwide. During feeding, aphids secrete salivary proteins with potential effector functions that play pivotal roles in plant–insect interactions. However, relatively few secreted proteins and effectors have been characterized in M. sorghi. In this study, proteomic analysis of aphid-infested sorghum leaves identified 69 putative aphid-derived proteins. Bioinformatic analyses were subsequently used to predict signal peptides within these proteins. Among the five candidates with signal peptides, MsSP1 was further confirmed to be delivered into sorghum tissues during aphid feeding by immunoblotting using a specific anti-MsSP1 antibody. Functional characterization revealed that silencing the MsSP1 gene in aphids by RNAi interference significantly reduced aphid fitness on sorghum. Moreover, transient expression of MsSP1 in Nicotiana benthamiana suppressed cryptogein-induced cell death and hydrogen peroxide accumulation, indicating that MsSP1 interferes with plant immune responses. Collectively, these results suggest that MsSP1 may act as a virulence effector that enhances aphid performance while suppressing host defense. This study expands current knowledge of plant–aphid interactions and provides new insights that may facilitate the development of sustainable pest-management strategies.

Insects doi: 10.3390/insects17080778

Authors: Jiaqiang Zhao Qiang Xu Guijie Chi Shengping Zhang Ruitao Yu Shihang Zhao Qi Gao Zhaohui Yang Guoliang Xu

Leucoptera malifoliella (Lepidoptera: Lyonetiidae) is a quarantine pest of apple and other Rosaceae fruit trees whose range is expanding into new territories. Its minute size and morphological overlap with closely related Lyonetiidae make routine identification unreliable, especially for larvae and damaged specimens. We compared COI sequences from six common small Lepidoptera species found in orchards and designed the species-specific primer pair SXW-F/SXW-R. The resulting polymerase chain reaction (PCR) assay amplifies an ~500 base pairs (bp) fragment exclusively from L. malifoliella; no product was detected in any of five non-target species. The reaction tolerates annealing temperatures of 50–58 °C and consistently detects the target across all life stages (first- to third-instar larvae, pupae, adults) and all adult tissues tested (antennae, head-thorax, abdomen, wings, legs). Detection sensitivity reaches 0.03 ng/μL—approximately one-thousandth of the DNA content of a single adult. This is the first species-specific COI (SS-COI) method reported for L. malifoliella. It furnishes a rapid, specific, and sensitive diagnostic tool for quarantine inspection, field monitoring, and integrated pest management (IPM) programs.

Insects doi: 10.3390/insects17080777

Authors: Muhammad Irfan Zafar Shaoshan Wang Qizhi Liu Jawad Hassan Talha Shafique Yuxian Liu

Research on insect biodiversity in arid and semi-arid agroecosystems of Central Asia remains limited, hindering the development of effective insect conservation strategies and integrated pest management (IPM) programs. This study examined insect community structure, diversity, and seasonal dynamics across three habitat types in Kekedala City, in the autonomous region of Ili Kazakh, Xinjiang, China. Solar-powered ultraviolet LED light traps (350–420 nm) were used for sampling from April to August 2024. A total of 63,090 individuals of 83 species, 57 families and 72 genera of insects were collected. Diversity indices calculated using the complete species dataset showed highest diversity in the riparian corridor (L3: H′ = 3.42, D = 0.962, S = 62), intermediate diversity in the agro-horticultural garden (L2: H′ = 3.18, D = 0.948, S = 54), and lowest diversity in the xerophytic shrubland (L1: H′ = 2.97, D = 0.935, S = 47). A supplementary analysis targeted a shared core assemblage of 17 species, defined as taxa captured at all three sampling sites with cumulative total abundances ranging from 50 to 100 individuals. This subset exhibited near-uniform diversity metrics across habitats (H′ = 2.83, D = 0.941, Pielou’s evenness J′ ≈ 1.0), a pattern driven by the prevalence of habitat generalists rather than capturing site-specific full community diversity. Two abundant pest species, Helicoverpa armigera (Hübner, 1808) (cotton bollworm, 5209 individuals, 8.3% of total) and Oryctes rhinoceros (Linnaeus, 1758) (rhinoceros beetle, 5206 individuals, 8.2% of total), both peaked in abundance in July–August; O. rhinoceros is associated with local ornamental and date palm plantings in the study area. In total, 15 major pest species were recorded. Mitochondrial cytochrome c oxidase subunit I (COI) DNA barcoding confirmed two new national insect records for China: Stethoconus pyri (Mella, 1861) (Hemiptera: Anthocoridae) and Pinacoplus didymogramma (Hampson, 1907) (Lepidoptera: Noctuidae). This study provides the first comprehensive baseline inventory of the insect fauna of Kekedala City. Descriptive ordination analyses suggest that habitat vegetation complexity may exert a stronger filtering effect on insect assemblage composition than the relatively small seasonal variation in temperature and humidity observed during the sampling period. As only a single trap was deployed within each habitat with no within-site replication, all cross-habitat community patterns reported herein are strictly descriptive and require validation via replicated field sampling in future research.

Insects doi: 10.3390/insects17080776

Authors: Lanmei Wei Minting Liang Xi Zeng Wancheng Liu Zhengwei Wu

To develop an efficient and low-toxic green plant-based insecticide and address the issues of rapid volatilization and poor stability of mint essential oil, this study prepared a mint essential oil nanemulsion composite formulation using Tween 80 as the surfactant and propylene glycol as the cosurfactant. The insecticidal activity of the formulation was tested against fall armyworm, Spodoptera frugiperda and corn aphid, Rhopalosiphum maidis. Results showed that the optimal formulation consisted of a surfactant to cosurfactant mass ratio of 3:1 and a mixed surfactant to mint essential oil mass ratio of 9:1. The formulation exhibited good stability after dilution and centrifugation tests. Bioactivity assays indicated that the formulation effectively inhibited and killed fall armyworm eggs. At a concentration of 6.66 mg/mL, it completely inhibited the hatching of fall armyworm eggs and achieved 100% mortality of corn aphid nymphs and adults. This mint essential oil nanemulsion composite formulation demonstrated excellent performance and significant bioactivity, providing a new formulation option and technical support for the green control of fall armyworm and aphids on corn.

Insects doi: 10.3390/insects17080775

Authors: Marzieh Kashkouli Jahangir Khajehali Mohammad Mehrabadi

Insect–microbe symbioses play pivotal roles in host ecology and plant–insect interactions, yet their species-specific functions in agricultural pests remain less understood. This study elucidates the functional role of symbiotic microbial communities in mediating insect host fitness and plant defense responses in two economically important whitefly species, Bemisia tabaci Gennadius and Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae). Using integrated molecular and physiological approaches, we characterized species-specific responses to antibiotic treatments (rifampicin and tetracycline) and their cascading effects on tripartite plant–insect–microbe interactions. In B. tabaci, antibiotic exposure induced significant depletion of the obligate symbiont Portiera and facultative Rickettsia (except for tetracycline-mediated Portiera proliferation), correlating with enhanced plant immune responses. In parallel, antibiotic treatments increased the titers of Hamiltonella and Rickettsia alongside constitutive plant defense suppression in T. vaporariorum, though tetracycline uniquely induced AOS expression elevation. Developmental assays revealed stage-specific vulnerabilities, with late nymphal and pupal stages showing high sensitivity to symbiont disruption, culminating in complete mortality within 40–50 d post-treatment. These findings show that microbial symbionts are essential to whitefly nutrition and evasion of plant anti-herbivore defenses. Our results provide a mechanistic basis for understanding symbiont-assisted invasion success in these whitefly species and underscore the potential of microbiome-targeted approaches for sustainable whitefly management.

Insects doi: 10.3390/insects17080774

Authors: Letícia Jansen Medeiros Michele Trombin de Souza Mireli Trombin de Souza Christian Peter Demari Gabriel Radtke Abib Leandro do Padro Ribeiro Vanessa Nogueira Soares Dori Edson Nava Daniel Bernardi

Tephritid flies, highlighting Anastrepha fraterculus and Ceratitis capitata, cause substantial economic losses and trigger strict quarantine measures worldwide. In response, research is looking for eco-friendly alternatives and, in this study, we evaluated 7 terpenes/terpenoids (α-pinene, β-pinene, β-caryophyllene, γ-terpinene, ρ-cymene, citronellal and geropine) and 3 phenylpropanoids (isoeugenol, methyl cinnamate and coumarin) commonly found in a diverse group of aromatic plants tested against A. fraterculus and C. capitata adults. Subsequently, their selectivity for the egg–larvae endoparasitoid Doryctobracon areolatus was also assessed. Ingestion and topical application bioassays (range = 100–6000 mg L−1) revealed that isoeugenol caused the highest mortality (≥75%) in both fruit fly species. Concentration–response indicated a similar toxicity of this compound to A. fraterculus (ingestion: LC50 ≅ 34.2 mg L−1, LC90 ≅ 105.7 mg L−1; topical: LC50 ≅ 33.7 mg L−1, LC90 ≅ 121.3 mg L−1) and C. capitata (ingestion: LC50 ≅ 33.2 mg L−1, LC90 ≅ 125.5 mg L−1; topical: LC50 ≅ 31.4 mg L−1, LC90 ≅ 129.2 mg L−1). None of the tested compounds (α-pinene, β-pinene, ρ-cymene, β-caryophyllene, isoeugenol, γ-terpinene, coumarin, citronellal, geropine and methyl cinnamate) reduced the number of oviposition punctures on grape berries by either fruit fly species. In contrast, all compounds caused lower mortality in D. aerolatus (≤17%) and did not impair parasitism, with a range of 43.21–62.13% among the tested compounds. Overall, our findings indicate that selected phytocompounds, particularly isoeugenol and citronellal, show strong insecticidal activity against A. fraterculus and C. capitata while having low toxicity to D. areolatus, supporting their use into sustainable pest management programs.

Insects doi: 10.3390/insects17080773

Authors: Yunqi Yang Shuying Dai Lizhen Zhang

Honeybees (Apis mellifera), as key pollinating insects, are undergoing population decline, which has become a critical environmental challenge affecting ecosystem stability and sustainable agriculture. Moreover, a potential association exists between the physiological and behavioral responses of honeybees induced by environmental stress and the pathological mechanisms of depression. The pathogenesis of depression remains complex and not fully understood, and a stable animal model is a prerequisite for investigating its mechanisms and screening antidepressants. This study aimed to examine the alterations induced by CUMS and to evaluate behavioral changes related to depression-like phenotypes and neurotransmitter levels in the honeybee brain. The results showed that CUMS treatment induced typical depression-like behaviors and downregulated monoamine neurotransmitters in honeybees, consistent with observations in mammalian depression models. Fluoxetine was found to reverse these abnormalities, further supporting the validity of the model. This study provides a novel tool for depression research, antidepressant screening, and stress-related investigations in pollinators.

Insects doi: 10.3390/insects17080772

Authors: Zhipeng He Boyang Zhang Rulin Wang Danping Xu Xinqi Deng Zhihang Zhuo

Spodoptera frugiperda is a highly polyphagous pest that poses a serious threat to global agricultural production. Understanding its species distribution is of great importance under the current context of climate change. In this study, we used the biomod2 platform to integrate six models, namely XGBOOST, Maxnet, Maxent, MARS, GBM, and GLM, to construct an ensemble model. This ensemble model was used to simulate the potential distribution of S. frugiperda under current and three future climate scenarios, and to analyze the main environmental factors influencing its distribution and their change trends. The results indicated that Bio08, Bio16, Bio09, and Bio03 were the major environmental factors affecting the species’ distribution. Under the current scenario, the suitable area was approximately 2026.05 × 104 km2, accounting for about 10% of the global land area, and was mainly concentrated in East Asia and central North America. The expansion of S. frugiperda varied among the three future climate scenarios; under the SSP5-8.5 scenario, the expansion toward higher latitudes was the most pronounced, with the total suitable area increasing by 91.8%. Analysis of the three climate scenarios revealed that the expansion trend of S. frugiperda intensified with increasing carbon emissions. Under the most conservative SSP1-2.6 scenario, even a slight reduction in suitable area was possible. This study provides an in-depth exploration of the distribution characteristics of S. frugiperda and its responses to environmental factors from a geographical perspective. These findings contribute to a better understanding of the species’ potential distribution and the influence of environmental variables from a spatial standpoint. They offer a scientific basis for the prevention and control of this pest in specific regions, and may also serve as a reference for future studies on similar invasive insect pests.

Insects doi: 10.3390/insects17080771

Authors: Weiqing Zheng Yinuo Yan Jingzhi Huang Siping Li Qianfeng Xia

Understanding how decomposing organic matter attracts calyptrate flies is fundamental to both medical entomology and forensic science, yet the differential effects of substrate type and decomposition stage remain poorly characterized in tropical environments. In this study, we established controlled decomposition gradients for fish viscera (animal tissue) and leafy vegetables (plant tissue) at 37 °C and 65% RH, defining six physicochemical stages per substrate based on color, odor, and ammonia emissions. Over 20 days, in Haikou, Hainan, we deployed 30 spatially replicated traps per stage, collecting 1538 specimens spanning 13 species across four families. Animal substrates attracted 6.8-fold higher fly densities than plant materials (1.48 vs. 0.22 flies/cage/hour; p < 0.01), with Limnophora nudiseta dominating animal-baited traps (68.43%) and Anthomyia illocata prevailing in plant traps (43.94%). Decomposition stage critically modulated attraction: mid–late decay stages (2–5) yielded 3.6-fold more flies on animal tissues than fresh stages, accompanied by a successional shift from A. illocata to L. nudiseta as the primary colonizer. Plant tissues showed incremental but non-significant density increases, and were consistently dominated by A. illocata. These findings demonstrate that substrate identity and decomposition dynamics jointly govern fly abundance, community composition, and niche partitioning. Our mechanistic framework offers practical guidelines for optimizing fly surveillance through species-specific bait selection and decay-stage calibration, with direct applications in vector control, public health monitoring, and forensic post mortem interval estimation.

Insects doi: 10.3390/insects17080770

Authors: Muhammad Faizal Zulkifli Jonathan Wee Kent Liew Meng Li Wong Lu Deng Cheong-Huat Tan

Mosquito pupae are conventionally believed to require water for survival and subsequent emergence into adult mosquitoes. This study assessed emergence of Ae. aegypti mosquitoes from four substrates: (1) water; (2) moist filter paper; (3) moist filter paper with a wet cotton pad below it; and (4) double-meshed wire surface with a wet tissue below it. High levels of emergence (at least 90%) were obtained for all four substrates. These mosquitoes displayed comparable fitness levels as represented by their flight ability and mating success. The median survival curve of male mosquitoes showed no significant differences, but significant differences were observed between groups of female mosquitoes that emerged from different substrates. The results will be helpful for programmes that intend to improve the logistical handling of mosquitoes for field releases.