Insects

15 pages, 2355 KB

Open AccessArticle

Identification of Central Regulatory Hubs in Pupal Diapause of Helicoverpa armigera Using Weighted Gene Co-Expression Network Analysis and Multiscale Embedded Network Analysis

by Zhe Song, Xinhui Liu, Jiawen Cao and Yujue Wang

Insects 2026, 17(3), 352; https://doi.org/10.3390/insects17030352 - 23 Mar 2026

Viewed by 807

Abstract

Diapause is a vital overwintering strategy for many insects, yet its comprehensive molecular architecture remains elusive. In the polyphagous pest Helicoverpa armigera, facultative pupal diapause is key to its ecological success. To elucidate the complex diapause regulatory network, we conducted a transcriptomic [...] Read more.

Diapause is a vital overwintering strategy for many insects, yet its comprehensive molecular architecture remains elusive. In the polyphagous pest Helicoverpa armigera, facultative pupal diapause is key to its ecological success. To elucidate the complex diapause regulatory network, we conducted a transcriptomic analysis of diapause (DP) versus non-diapause (NP) pupal brains across early pupal development (days 2, 5, and 10). Integrated analyses, including differential expression, persistent gene identification, weighted gene co-expression network analysis (WGCNA), and multiscale embedded network analysis (MEGENA), were employed to define core regulatory modules and hubs. The number of differentially expressed genes (DEGs) increased over time, with 1781 genes persistently regulated across all time points, enriched in mitochondrial metabolism, hormone signaling, and chromatin remodeling. WGCNA revealed a diapause-associated module (red) linked to RNA processing/transcription and a development-associated module (blue) enriched for translation and mitochondrial metabolism. Network analyses pinpointed three central hub genes: DDX5 and PLK4 (downregulated in diapause, upregulated upon 20E treatment) and TAF5L (upregulated in diapause, downregulated after 20E). This study provides a systems-level view of the transcriptional landscape governing pupal diapause in H. armigera and identifies novel candidate regulators for future functional studies. Full article

(This article belongs to the Section Insect Molecular Biology and Genomics)

► Show Figures

Figure 1

14 pages, 1060 KB

Open AccessArticle

Evaluation of Novel Dillapiol Analogs as Insect Detoxification Enzyme Inhibitors and Insecticide Synergists

by Suqi Liu, Ana Francis Carballo-Arce, Zhiling Wang, Tony Durst, Steven R. Sims, John T. Arnason and Ian M. Scott

Insects 2026, 17(3), 351; https://doi.org/10.3390/insects17030351 - 23 Mar 2026

Viewed by 730

Abstract

Dillapiol is a naturally occurring methylenedioxyphenyl compound with insecticide-synergizing activity comparable to piperonyl butoxide (PBO). This study identified structurally related molecules with practical potential for managing insecticide-resistant insects. Six new dillapiol analogs, containing ester- or ether-linked side chains, were synthesized and evaluated as [...] Read more.

Dillapiol is a naturally occurring methylenedioxyphenyl compound with insecticide-synergizing activity comparable to piperonyl butoxide (PBO). This study identified structurally related molecules with practical potential for managing insecticide-resistant insects. Six new dillapiol analogs, containing ester- or ether-linked side chains, were synthesized and evaluated as pyrethrum synergists against the Colorado potato beetle (CPB) Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae). Their activity was assessed through bioassays and by quantifying inhibition of Phase I and II detoxification enzymes in vitro and in vivo. All six compounds displayed higher synergistic activity by ingestion than by topical exposure, and each structural class included at least one compound with a synergism ratio greater than 20. In the resistant CPB strain (RS-CPB), two ester compounds inhibited P450 monooxygenase activity in vitro as effectively as PBO, while dillapiol and one ether analog reduced P450 activity in vivo. Notably, all six analogs reduced glutathione S-transferase (GST) activity; the most active was an ether analog with an in vitro IC₅₀ of 0.23 (±0.04) mM. Dillapiol also significantly reduced GST activity in vivo. These analogs demonstrated PBO-equivalent P450 inhibition combined with unique GST inhibition and show promise as alternative synergists for managing insecticide-resistant insects. Full article

(This article belongs to the Topic Exploring Plant-Derived Compounds for Effective Insect Pest Management in Agriculture)

► Show Figures

Graphical abstract

12 pages, 1393 KB

Open AccessArticle

Fertility and Viability of Hybrid Offspring Imply the Absence of Major Postzygotic Isolation Between Two Reticulitermes Termite Species

by Jia Wu, Yonghui Wang, Bei Du and Xiaolan Wen

Insects 2026, 17(3), 350; https://doi.org/10.3390/insects17030350 - 23 Mar 2026

Viewed by 752

Abstract

(1) Reproductive isolation serves as a critical mechanism that prevents interspecific hybridization among closely related species, thereby preserving species integrity. In termites, hybridization between certain closely related species can overcome prezygotic isolation and produce offspring. However, whether these hybrids can overcome postzygotic barriers [...] Read more.

(1) Reproductive isolation serves as a critical mechanism that prevents interspecific hybridization among closely related species, thereby preserving species integrity. In termites, hybridization between certain closely related species can overcome prezygotic isolation and produce offspring. However, whether these hybrids can overcome postzygotic barriers remains substantially underexplored. (2) This investigation conducted a comparative analysis of reproductive output (egg production and offspring count), physiological traits (body weight), functional characteristics (locomotor capacity), and hybrid fertility between the hybrid colony that was established by Reticulitermes flaviceps and R. chinensis and the conspecific pairing colonies of R. flaviceps and R. chinensis, respectively. (3) The results showed that hybrid colonies laid significantly more eggs and produced significantly more larvae than conspecific colonies. The hybrid offspring showed no decline in weight and locomotor capacity. Furthermore, the hybrid offspring maintained balanced sex ratios with unimpaired caste differentiation and fertility in both sexes. (4) These results demonstrate that the prezygotic reproductive isolation mechanism is incomplete between two closely related termite species, and there is a risk of forming hybrid populations. This work not only provides a theoretical basis for monitoring the risk of hybrid populations in termite management but also offers new insights into the evolution of reproductive isolation and speciation in social insects. Full article

(This article belongs to the Section Insect Pest and Vector Management)

► Show Figures

Figure 1

19 pages, 2362 KB

Open AccessArticle

Assessment of Ubiquitous Promoters Driving Fluorescent Marker and Transposase Expression to Develop a High-Performance piggyBac Transgenic System in Bactrocera dorsalis

by Helin Jiang, Yulun Wu, Jun Cai, Xianwu Lin and Rihui Yan

Insects 2026, 17(3), 349; https://doi.org/10.3390/insects17030349 - 23 Mar 2026

Viewed by 701

Abstract

Bactrocera dorsalis (oriental fruit fly) is a destructive invasive pest threatening global agriculture. Although integrated pest management is applied, environmentally friendly genetic control methods are urgently needed. The development of such methods particularly relies on efficient genetic elements. In this study, we compared [...] Read more.

Bactrocera dorsalis (oriental fruit fly) is a destructive invasive pest threatening global agriculture. Although integrated pest management is applied, environmentally friendly genetic control methods are urgently needed. The development of such methods particularly relies on efficient genetic elements. In this study, we compared the transient expression of mScarlet-I driven by various Actin and PUb promoters in B. dorsalis embryos. The truncation of two strong promoters, BdActA3a and BdPUb, revealed that the 5.0-kb BdActA3a and 3.6-kb BdPUb promoters drove significantly higher expression than their truncated variants. Notably, the BdPUb promoter was highly effective in driving fluorescent protein expression in B. dorsalis. Using the 3.6-kb BdPUb promoter, we constructed a transposase plasmid BdPUb-3.6 kb>hyPBase. By co-injecting the BdPUb 3.6kb>mScarlet-I donor construct, we successfully generated a fluorescent transgenic strain with a transgenic efficiency of approximately 26%. The strain exhibited stage-specific fluorescence and maternal effect and the homozygotes showed fecundity comparable to wild-type controls. The high performance of the piggyBac transposase and the fluorescence screening system provides a substantial technical foundation for basic research and future development of genetically modified strains to control B. dorsalis. Full article

(This article belongs to the Topic Advances in Integrated Pest Management: New Tools and Tactics for Pest Control)

► Show Figures

Figure 1

21 pages, 4330 KB

Open AccessArticle

Spatial Differentiation and Environment-Driven Mechanisms of Locust Community Structure in the Xinjiang Region Along the Sino-Kazakh Border

by Siqi Lin, Yongjun Zhang, Yating Guo, Huixia Liu, Jun Lin, Rong Ji, Roman Jashenko and Lan He

Insects 2026, 17(3), 348; https://doi.org/10.3390/insects17030348 - 22 Mar 2026

Viewed by 556

Abstract

This study was conducted in the Xinjiang region, China, along the Sino-Kazakh border, an area recognized as high-risk for locust outbreaks and characterized by ongoing shifts in dominant pest species. This study systematically examined the structural characteristics of locust communities across different grassland [...] Read more.

This study was conducted in the Xinjiang region, China, along the Sino-Kazakh border, an area recognized as high-risk for locust outbreaks and characterized by ongoing shifts in dominant pest species. This study systematically examined the structural characteristics of locust communities across different grassland types and identified the underlying environmental driving mechanisms. Field surveys were conducted to assess the diversity characteristics, density variations, and niche width of the locust communities across the different grassland types. The locust community in the mountain meadows had a significantly lower Shannon diversity index compared with the other grassland types (p < 0.05). Although the Simpson dominance index and Pielou evenness index were also the lowest in the mountain meadows, these differences were not statistically significant (p > 0.05). Permutational multivariate analysis of variance (PermANOVA) revealed highly significant differences in locust density among the grassland types (p = 0.001). Ecological niche analysis revealed stronger interspecific competition in the lowland meadow, and weaker competition in the temperate steppe-enriched deserts and temperate desert grasslands. Structural equation modeling and random forest analysis identified soil organic, plant total potassium, and soil pH as the key factors driving locust community structure across grassland types. This study clarifies the diversity patterns of locust communities in the Xinjiang region along the Sino-Kazakh border and provides empirical data to better understand locust community structure and distribution. It also offers a scientific basis for developing sustainable locust management strategies. Full article

(This article belongs to the Section Insect Ecology, Diversity and Conservation)

► Show Figures

Figure 1

11 pages, 245 KB

Open AccessArticle

Comparative Efficacy of Carbonyl Sulfide Against Phosphine-Resistant and Phosphine-Susceptible Strains of the Rice Weevil Sitophilus oryzae

by Bong-Su Kim, Ji-Eun Choi, Jae-Ho Ban, Soo-Jung Suh and Jun-Ran Kim

Insects 2026, 17(3), 347; https://doi.org/10.3390/insects17030347 - 21 Mar 2026

Cited by 1 | Viewed by 598

Abstract

Recently, the occurrence of phosphine-resistant pests has been increasingly reported in many countries. In this study, the efficacy of carbonyl sulfide (COS) on phosphine-resistant and phosphine-susceptible strains of the rice weevil, Sitophilus oryzae, was evaluated to determine the applicability of COS as [...] Read more.

Recently, the occurrence of phosphine-resistant pests has been increasingly reported in many countries. In this study, the efficacy of carbonyl sulfide (COS) on phosphine-resistant and phosphine-susceptible strains of the rice weevil, Sitophilus oryzae, was evaluated to determine the applicability of COS as a fumigant to control phosphine resistance. S. oryzae at the egg, larval and adult stages was treated with phosphine and COS to determine the 50 and 99% lethal concentration time (LCt₅₀ and LCt₉₉, respectively) values. The LCt₅₀ values of phosphine for phosphine-susceptible S. oryzae at the egg, larval and adult stages were 1.44, 0.63, and 0.66 mg h/L, respectively, and those for phosphine-resistant S. oryzae were 30.65, 17.60, and 8.37 mg h/L, respectively. In contrast, the LCt₅₀ values of COS for phosphine-susceptible S. oryzae at the egg, larval, and adult stages were 284.19, 171.11 and 212.55 mg h/L, respectively, and those for phosphine-resistant S. oryzae were 289.78, 149.87 and 229.06 mg h/L, respectively. The COS-resistance ratios were 1.02, 0.88, and 1.08 for S. oryzae at the egg, larval, and adult stages, respectively. These results indicate that the efficacy of COS is similar for phosphine-susceptible and phosphine-resistant pests, suggesting that COS can be used to control phosphine-resistant grain pests. Full article

(This article belongs to the Special Issue Integrated Pest Management in Stored Products)

17 pages, 1141 KB

Open AccessArticle

Lethal and Sublethal Effects of Selected Insecticides on the Eggs of the Predatory Bug Orius niger

by Isse Hassan Ali and Utku Yükselbaba

Insects 2026, 17(3), 346; https://doi.org/10.3390/insects17030346 - 21 Mar 2026

Viewed by 724

Abstract

The compatibility of insecticides with biological control agents is a critical component of integrated pest management (IPM). In this study, the lethal and sublethal effects of acrinactrin, chlorantraniliprole, flupyradifurone, pyriproxyfen, spinosad, and spiromesifen on the egg stage of Orius niger (Wollf) (Hemiptera: Anthocoridae) [...] Read more.

The compatibility of insecticides with biological control agents is a critical component of integrated pest management (IPM). In this study, the lethal and sublethal effects of acrinactrin, chlorantraniliprole, flupyradifurone, pyriproxyfen, spinosad, and spiromesifen on the egg stage of Orius niger (Wollf) (Hemiptera: Anthocoridae) were evaluated under laboratory conditions. Egg hatchability, immature survival, reproductive performance, and population parameters were analyzed using the age-stage, two-sex life table. Egg hatchability was lowest in the acrinactrin treatment (51%) and highest in the pyriproxyfen treatment (93%). Nymphal survival varied from 0% to 80%, with acrinactrin causing complete mortality and a significant reduction in spinosad, while the highest nymphal survival and population growth was recorded in spiromesifen treatment. The intrinsic rate of increase (r, day⁻¹) was 0.00, 0.05, 0.05, 0.08, 0.004, and 0.06 for acrinactrin, chlorantraniliprole, flupyradifurone, pyriproxyfen, spinosad, and spiromesifen, respectively, while fecundity (F, eggs female⁻¹) values were 0, 15.20, 15.83, 42.32, 10.37, and 21.85, respectively. According to the International Organization for Biological Control (IOBC) classification, acrinactrin was harmful, spinosad moderately harmful, and the remaining insecticides slightly harmful to O. niger eggs. Pyriproxyfen and spiromesifen were the most compatible with IPM programs. Caution is warranted for chlorantraniliprole due to its effects on reproductive parameters, whereas spinosad and acrinactrin should be avoided on O. niger eggs. Full article

(This article belongs to the Section Insect Physiology, Reproduction and Development)

► Show Figures

Figure 1

15 pages, 15887 KB

Open AccessArticle

Morphology of the Larval Antennae and Mouthparts in Conogethes punctiferalis (Guenée) (Lepidoptera: Crambidae) with Special Reference to Sensilla

by Chao Yue, Shang Shi, Yaqian Shi, Peiyu Chen, Ting Lei and Na Ma

Insects 2026, 17(3), 345; https://doi.org/10.3390/insects17030345 - 21 Mar 2026

Cited by 1 | Viewed by 623

Abstract

The yellow peach moth, Conogethes punctiferalis, is a destructive polyphagous pest and poses a severe threat to the fruit industry and field crops worldwide with its continuously increasing population and expanding host range in recent years. Despite the severe damage caused by [...] Read more.

The yellow peach moth, Conogethes punctiferalis, is a destructive polyphagous pest and poses a severe threat to the fruit industry and field crops worldwide with its continuously increasing population and expanding host range in recent years. Despite the severe damage caused by C. punctiferalis larvae, their antennae and mouthparts, equipped with abundant sensilla responsible for feeding behavior, have not been investigated in detail. In our study, the antennae, mouthparts, and associated sensilla of first-instar and mature larvae of C. punctiferalis were examined with light and scanning electron microscopy. Our results revealed no obvious morphological differences between the two instars in the basic composition of the antennae and mouthparts, or in the types, distribution, and numbers of sensilla. The antenna is three-segmented, with no sensilla on the scape, three sensilla basiconica and two sensilla chaetica on the pedicel, and three sensilla basiconica and one sensillum styloconicum on the flagellum. The mouthparts of C. punctiferalis are typically mandibulate and consist of a labrum-epipharynx, paired mandibles, a pair of maxillae, a labium, and a hypopharynx. Six types of sensilla were primarily concentrated on the labrum-epipharynx, maxilla, and labial palp, including sensilla chaetica, sensilla basiconica, sensilla styloconica, sensilla digitiformia, sensilla epipharyngea, and sensilla placodea. We conducted a systematic analysis of the characteristics of sensilla and discussed their variation in the context of Lepidoptera phylogeny. The potential functions of the sensilla have also been inferred. The study could advance our understanding of the behavioral ecology of C. punctiferalis and provide potentially useful information on the development of pest control technologies. Full article

(This article belongs to the Special Issue Insect Sensory Biology—2nd Edition)

► Show Figures

Figure 1

16 pages, 2493 KB

Open AccessArticle

Determination of the Morphometric Characteristics of Larval Instars in the Sap Beetle Urophorus humeralis (Coleoptera: Nitidulidae)

by Kang Chang, Yilin Guo, Youssef Dewer, Xiaoxiao Chen and Suqin Shang

Insects 2026, 17(3), 344; https://doi.org/10.3390/insects17030344 - 21 Mar 2026

Viewed by 677

Abstract

Effective integrated pest management (IPM) relies on precise knowledge of pest developmental biology, particularly the identification of larval instars, which is fundamental for predicting population dynamics and timing control interventions. This study established a morphometric framework for the larval staging of a sap [...] Read more.

Effective integrated pest management (IPM) relies on precise knowledge of pest developmental biology, particularly the identification of larval instars, which is fundamental for predicting population dynamics and timing control interventions. This study established a morphometric framework for the larval staging of a sap beetle pest infesting pear orchards. Specimens were collected and reared under laboratory conditions, with their identity confirmed as Urophorus humeralis through integrated morphological and molecular (COI barcoding) analysis. To determine the number of larval instars, head capsule width (HCW), inter-antennal distance (IAD), and inter-caudal distance (ICD) were measured. Frequency distribution analysis and validation using Dyar’s rule via linear regression revealed three distinct larval instars. Head capsule width was identified as the most reliable and consistent morphological character for instar discrimination. This study reports for the first time the infestation of pear fruits by U. humeralis and provides detailed morphometric criteria for larval staging, delivering essential baseline data for the biology of Nitidulidae and a scientific basis for developing stage-specific pest management strategies. Full article

(This article belongs to the Special Issue Revival of a Prominent Taxonomy of Insects—2nd Edition)

► Show Figures

Figure 1

17 pages, 2582 KB

Open AccessArticle

Function of HIF-1α in Regulation of Antioxidative Stress of Tribolium castaneum Under Hypoxia

by Zhichao Wan, Xiao Li, Yun Wang, Shiyuan Miao, Zhiteng Chen, Sufen Cui and Yujie Lu

Insects 2026, 17(3), 343; https://doi.org/10.3390/insects17030343 - 21 Mar 2026

Viewed by 659

Abstract

Hypoxia-inducible factor (HIF) is recognized as a key transcription factor via regulating a variety of molecular responses to hypoxia, although the details are still unclear. In this study, based on bioinformatics analysis, the expression of the HIF-1α gene in T. castaneum (TcHIF-1α [...] Read more.

Hypoxia-inducible factor (HIF) is recognized as a key transcription factor via regulating a variety of molecular responses to hypoxia, although the details are still unclear. In this study, based on bioinformatics analysis, the expression of the HIF-1α gene in T. castaneum (TcHIF-1α) under hypoxic treatments was determined. After TcHIF-1α knockdown by injecting dsRNA, larval mortality, the expression levels of oxidative stress-related genes, and enzymatic activities were measured; DNA damage was also evaluated through single cell gel electrophoresis. The result indicated that TcHIF-1α is highly conserved in structure. TcHIF-1α exhibited distinct temporal patterns, with a peak after 72 h of exposure to 2% O₂. Following TcHIF-1α knockdown, a significant increase in larval mortality (17.44 ± 5.91%) and moderate DNA damage level was found. This might be accompanied by ROS accumulation, lipid peroxidation (LPO), and suppression of antioxidant enzymatic activities. The expression of genes involved in ROS synthesis (e.g., NOX) was significantly upregulated, whereas genes responsible for mitigating oxidative stress (e.g., OGG1, XRCC1, PARP1, SOD1a) were markedly downregulated. These findings elucidate the critical role of HIF-1α in insect hypoxia adaptation by regulating the antioxidative stress, highlighting its potential as a promising target for developing novel pest control strategies. Full article

(This article belongs to the Special Issue Insect Adaptive Dynamics in a Changing Environment)

► Show Figures

Graphical abstract

16 pages, 1265 KB

Open AccessArticle

Optimizing Rearing of Helicoverpa zea: Impacts of Pupal Maturity, Emergence Synchrony, and Adult Cohort Size

by Shucong Lin, Tiago Silva, Bhavana Patla, Graham P. Head and Fangneng Huang

Insects 2026, 17(3), 342; https://doi.org/10.3390/insects17030342 - 20 Mar 2026

Viewed by 606

Abstract

The bollworm/corn earworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), is one of the most economically damaging crop pests in North America. Colonies of H. zea are notoriously difficult to maintain and frequently collapse in laboratory rearing. The persistent difficulty in maintaining healthy H. zea [...] Read more.

The bollworm/corn earworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), is one of the most economically damaging crop pests in North America. Colonies of H. zea are notoriously difficult to maintain and frequently collapse in laboratory rearing. The persistent difficulty in maintaining healthy H. zea colonies has become a major obstacle to performing many research activities on the insect. To optimize colony maintenance, six populations were evaluated across three trials and six tests examining pupal maturity at diet removal, adult emergence synchrony, and cohort size at mating and reproduction. Females emerging from mature pupae produced more eggs than those from mid-aged (5–7 d) or young pupae (0–2 d). Synchronizing male and female emergence within one day yielded higher mating frequency, spermatophore transfer, and progeny, whereas a two-day difference reduced these metrics by 45–67%. Adult cohort size also influenced the outcomes, with ≥10 males and ≥10 females per cage enhancing reproductive success. Most matings occurred on nights 2–3, peaking within 2.5 h after lights off. Positive correlations were observed among mating frequency, spermatophore transfer, and progeny production. Overall, optimal performance was achieved by removing pupae only at maturity, synchronizing adult emergence within one day, and maintaining larger adult cohorts. These findings should establish key conditions to improve the mating success, reproduction, and laboratory rearing of H. zea. Full article

(This article belongs to the Section Insect Physiology, Reproduction and Development)

► Show Figures

Figure 1

24 pages, 8107 KB

Open AccessArticle

Seasonal and Interannual Variability in the Insect Pest Damage and Beneficial Insect Populations Across Apple Orchards of Different Ages

by Kornél Komáromi, Mihály Zalai, Ágnes Kukorellyné Szénási and Zita Dorner

Insects 2026, 17(3), 341; https://doi.org/10.3390/insects17030341 - 20 Mar 2026

Viewed by 681

Abstract

Apple is one of the most important fruits worldwide; in addition, it constitutes nearly 60% of Hungary’s total fruit production. Presently, the challenge in pest management is not only the decreased range of pesticides, but also the deeper knowledge of natural enemies occurring [...] Read more.

Apple is one of the most important fruits worldwide; in addition, it constitutes nearly 60% of Hungary’s total fruit production. Presently, the challenge in pest management is not only the decreased range of pesticides, but also the deeper knowledge of natural enemies occurring in fruit plantations, and in their neighborhood. Our objective was to study how season, year, orchard structure, and varieties influence the occurrence of insect pest damage and beneficial insects in apple. We also investigated the strength of correlations between pest damage and natural enemies, as well as among the different natural enemy taxa. The experiment was conducted in three apple orchards, and the damage of insect pests and the number of natural enemies were monitored across ten trees/varieties/sectors/dates. All sites were managed according to integrated pest management (IPM) guidelines, and no unmanaged or untreated control plots were included. Significant differences were observed among orchards and years for all taxa, except Cydia pomonella (L.) among orchards and Orius spp. among years. Pest populations are primarily driven by seasonal and climatic factors, while beneficial insects are shaped more by local habitat features and orchard structure. No effect of the varieties on insect damage could be detected, whereas the abundance of beneficial organisms differed significantly among varieties in more cases. The weak correlations between pests and their natural enemies suggest that the presence and activity of predators depend not only on pest abundance but also on other interrelated ecological factors in intensive apple orchards. The damage caused by C. pomonella could also be kept at a low level in all orchards when appropriate pest management technology is applied. Full article

(This article belongs to the Special Issue Insects Ecology and Biological Control Applications)

► Show Figures

Figure 1

15 pages, 26045 KB

Open AccessArticle

Morphological and Ultrastructural Characterization of the Venom Apparatus of the Predatory Stink Bug, Arma custos

by Yuqin Wang, Ping Gao, Chaoyan Wu, Wenxiu Wang and Jiaying Zhu

Insects 2026, 17(3), 340; https://doi.org/10.3390/insects17030340 - 20 Mar 2026

Viewed by 546

Abstract

The predatory bug Arma custos (Hemiptera: Pentatomidae) is a natural enemy insect capable of preying on over 40 types of agricultural and forestry pests. Here, we describe the characteristics of the morphology and ultrastructure of its venom apparatus visualized using light and electron [...] Read more.

The predatory bug Arma custos (Hemiptera: Pentatomidae) is a natural enemy insect capable of preying on over 40 types of agricultural and forestry pests. Here, we describe the characteristics of the morphology and ultrastructure of its venom apparatus visualized using light and electron microscopy. Light microscopy revealed that the venom apparatus of A. custos consists of a pair of main gland and tubular accessory gland. The main gland consist of two lobes, the anterior main gland (AMG) and posterior main gland (PMG). Between the two lobes of the main gland, there is a strong constriction, characterizing a hilum (Hi) where two separate ducts, the venom duct of the main gland (VD) and the duct connecting the accessory gland to the main gland (AMD), are inserted. The VD extends toward the head and connects to the venom pump (VP), while the AMD extends toward the thorax and connects to the accessory gland (AG). Ultrastructural examination of the venom glands reveals that the AMG and PMG consist of a layer of cubic or spherical glandular cells forming a large circular lumen, while the AG exhibits two narrow lumens. The secretory cytoplasm of AMG, PMG, and AG contains a well-developed rough endoplasmic reticulum, along with mitochondria, nuclei, secretory vesicles, autophagosomes, and secretory granules. However, significant differences exist in the ultrastructural characteristics among the three glands. Unlike glandular secretory cells in the venom glands, the ultrastructure of VD, and AMD reveals only well-developed nuclei, mitochondria, and elaborate plasma membrane folds. These results indicate that venom proteins are synthesized and stored by the AMG, PMG, and AG, while the VD and AMD ducts are responsible for transporting the venom. Full article

(This article belongs to the Section Insect Physiology, Reproduction and Development)

► Show Figures

Figure 1

12 pages, 4510 KB

Open AccessArticle

Silencing Attempts of Bombyx mori Odorant Receptors Potentially Associated with Oviposition Behavior

by Chanikarn Navakeatpreecha, Piriya Putanyawiwat, Fah Lertkulvanich, Jutarat Jamkratoke, Banthari Chotimanothum and Anchanee Kubera

Insects 2026, 17(3), 339; https://doi.org/10.3390/insects17030339 - 20 Mar 2026

Viewed by 668

Abstract

The silkworm, Bombyx mori (Bm), is an insect that contributes to industries such as silk production, cosmetics, medicine, and food, as well as to scientific research. A previous study showed that Bm odorant receptor (BmOr) genes, BmOr44, BmOr54 [...] Read more.

The silkworm, Bombyx mori (Bm), is an insect that contributes to industries such as silk production, cosmetics, medicine, and food, as well as to scientific research. A previous study showed that Bm odorant receptor (BmOr) genes, BmOr44, BmOr54, and BmOr63, may play a major role in oviposition. This research aimed to investigate the function of these three genes using a double-stranded RNA (dsRNA) technique to knock down their expression levels. Our results revealed that the gene-specific dsRNAs could moderately reduce the expression levels of BmOr44, BmOr54, and BmOr63 in the silk moth antenna. Silk moths were injected with 50 nM dsRNABmOr54 and 100 nM dsRNABmOr63 and showed relative oviposition rates under the mulberry leaves condition at 111.45% and 109.58%, respectively, when compared to those with dsRNAlacZ injection. The reduction in expression levels of these three genes showed no effect on the oviposition rates of the silk moths without mulberry leaves treatment. The expression levels of these BmOr genes were restored after fertilization, suggesting the temporary effects of the dsRNAs. Our findings suggested that variation in BmOr54 expression level was correlated with changes in oviposition behavior in Bombyx mori. Full article

(This article belongs to the Special Issue Genomics and Molecular Biology in Silkworm)

► Show Figures

Graphical abstract

15 pages, 1523 KB

Open AccessArticle

Unexpected Persistence of the Predatory Mite Amblyseius andersoni Under Insecticide Exposure in Italian Apple Orchards

by Guillaume Serra, Letizia Ripamonti, Venkata Avinash Addanki, Paola Tirello, Carlo Duso and Alberto Pozzebon

Insects 2026, 17(3), 338; https://doi.org/10.3390/insects17030338 - 20 Mar 2026

Viewed by 755

Abstract

Predatory mites are key natural enemies in perennial crops, and their conservation is fundamental to ensure biocontrol of several pests. Yet their susceptibility to insecticides may compromise their role in Integrated Pest Management (IPM). In the past, pyrethroids proved to be poorly selective [...] Read more.

Predatory mites are key natural enemies in perennial crops, and their conservation is fundamental to ensure biocontrol of several pests. Yet their susceptibility to insecticides may compromise their role in Integrated Pest Management (IPM). In the past, pyrethroids proved to be poorly selective insecticides towards predatory mites, but in various countries their use recently increased in fruit orchards to counteract invasive pests. In this study, we assessed the effects of pyrethroids on the predatory mite Amblyseius andersoni through field experiments in apple orchards and laboratory assays on different strains. Field trials showed that A. andersoni populations remained unaffected by pyrethroid applications. Laboratory assays revealed intraspecific variation in A. andersoni populations: one commercial strain was highly susceptible to deltamethrin, whereas other commercial or field-collected strains were not affected, with no apparent sub-lethal effect on fecundity. These results underscore the contrasting susceptibility among predatory mite strains. From an IPM perspective, the lack of susceptibility to pyrethroids in A. andersoni may sustain biological control where insecticide use is unavoidable. Our findings stress the importance of evaluation procedures in toxicological studies, in particular the need to compare different strains, and of further investigation on predatory mite resistance. The implications for conservation programs in perennial cropping systems are addressed hereafter. Full article

(This article belongs to the Section Insect Pest and Vector Management)

► Show Figures

Figure 1

24 pages, 3048 KB

Open AccessArticle

Mitogenomic Insight into the Population Genetic Diversity and Phylogeography of Soybean Stink Bug (Riptortus pedestris) in China

by Yuxin Zhou, Shusen Shi, Lei Chen, Zhengxiao Du, Yuan Chen, Junkui Ma, Wenbin Wang, Lulu Wang, Yinyue Zhao, Shiyu Zhu and Yu Gao

Insects 2026, 17(3), 337; https://doi.org/10.3390/insects17030337 - 19 Mar 2026

Cited by 2 | Viewed by 812

Abstract

Riptortus pedestris (Hemiptera, Alydidae) is widely distributed across East Asia, where significant genetic differentiation may occur among geographic populations. To understand the genetic structure, historical dynamics, and formation of geographic distribution patterns in China, we conducted a phylogeographic analysis using three mitochondrial genes [...] Read more.

Riptortus pedestris (Hemiptera, Alydidae) is widely distributed across East Asia, where significant genetic differentiation may occur among geographic populations. To understand the genetic structure, historical dynamics, and formation of geographic distribution patterns in China, we conducted a phylogeographic analysis using three mitochondrial genes (COI, COII, Cytb) from 35 populations. After PCR amplification, we performed genetic diversity analysis, Fst/Nm estimation, phylogenetic reconstruction (ML, BI, NJ), haplotype network, AMOVA, neutrality tests, mismatch distribution, and molecular dating. Results revealed high genetic diversity (Hd > 0.81, π > 0.011), an AT-rich base composition, and faster evolution at the first codon position. Genetic and geographic distances were significantly correlated, with high Fst values indicating strong differentiation, especially between southwestern/southern and other populations. Two main clades were identified: Clade 1 (mainly southern and southwestern China) and Clade 2 (central, northern, northwestern, and northeastern China). A star-like haplotype network and neutrality tests suggested a rapid expansion around 0.019–0.022 Ma (Last Glacial Maximum), and molecular dating estimated the main split at ~0.029 Ma. AMOVA and Gst/Nst confirmed significant phylogeographic structure with most variation among populations. This study provides initial evidence for the genetic differentiation and evolutionary history of R. pedestris in China, demonstrating that its population structure was shaped by climatic changes and geographical isolation, providing key insights into its adaptive evolution and dispersal. Full article

(This article belongs to the Topic Sustainable Utilization of Insect Biodiversity in Agriculture Forestry and Food Systems Resource Utilization, Food Security and Policy Integration)

► Show Figures

Graphical abstract

26 pages, 2294 KB

Open AccessReview

How Environmental and Ecological Stressors Reprogram Honey Bee Chemistry Through the Microbiome–Metabolome Axis

by Yahya Al Naggar, Hamed A. Ghramh, Amira Elfarnawany and Amr Mohamed

Insects 2026, 17(3), 336; https://doi.org/10.3390/insects17030336 - 19 Mar 2026

Viewed by 1113

Abstract

Honey bees are exposed to a wide range of environmental and ecological stressors that threaten individual health and colony sustainability. Growing evidence suggests that many of these stressors converge on a common target: the gut microbiome and its metabolic functions. The honey bee [...] Read more.

Honey bees are exposed to a wide range of environmental and ecological stressors that threaten individual health and colony sustainability. Growing evidence suggests that many of these stressors converge on a common target: the gut microbiome and its metabolic functions. The honey bee microbiome–metabolome axis represents a central regulatory system linking microbial symbionts with host nutrition, detoxification, immune competence, neural signaling, and social behavior. This review synthesizes current knowledge on how major stressors—including pesticides, antibiotics, pathogens, nutritional imbalance, thermal stress, habitat change, and environmental contaminants—reprogram honey bee chemistry by disrupting microbial community structure and, importantly, microbial and host metabolic pathways. We highlight recurring patterns consistent with functional dysbiosis, characterized by impaired energy metabolism, reduced production of short-chain fatty acids, altered amino acid and lipid metabolism, compromised antioxidant and detoxification capacity, and weakened immune regulation. However, much of the current evidence is correlative and derived from short-term or laboratory-focused studies; longitudinal and multi-site field validation of causal links remains limited. Importantly, emerging multi-omics studies suggest that profound metabolic disturbances can occur even when taxonomic changes in the microbiome are modest, emphasizing the need to move beyond descriptive community profiling toward functional and mechanistic assessments. We further discuss how stress-induced metabolic reprogramming at the individual level scales up to influence behavior, division of labor, and colony-level resilience. Finally, we propose a conceptual model illustrating how diverse stressors converge to disrupt the microbiome–metabolome axis, potentially leading to functional dysbiosis and host impairment. Full article

(This article belongs to the Special Issue Honeybee and Other Pollinators: Physiology and Biochemistry Across Environmental Conditions)

► Show Figures

Graphical abstract

16 pages, 1059 KB

Open AccessArticle

Cold Disinfestation of Zeugodacus tau (Diptera: Tephritidae) on Oranges Using Artificial Infestation Method

by Jiajiao Wu, Mutao Wu, Lixia Feng, Weisong Li, Zhihong Li, Qiang Xu, Haijun Liu, Tao Liu and Sihua Yang

Insects 2026, 17(3), 335; https://doi.org/10.3390/insects17030335 - 19 Mar 2026

Viewed by 551

Abstract

Zeugodacus tau, an economically important fruit fly species, exhibits a preference for infesting the fruits of cucurbitaceae, but it has also been reared from the fruits of several other plant families. Phytosanitary treatments are needed to ship the fruit from some of [...] Read more.

Zeugodacus tau, an economically important fruit fly species, exhibits a preference for infesting the fruits of cucurbitaceae, but it has also been reared from the fruits of several other plant families. Phytosanitary treatments are needed to ship the fruit from some of these host plants out of areas where populations of the fruit fly exist. Based on the guidelines for the development of cold disinfestation treatments for fruit fly host commodities, proposed by the International Plant Protection Convention (IPPC), the cold disinfestation trials were carried out with Z. tau infesting oranges through artificial infestation. The results showed that the third instar of Z. tau was the most tolerant stage among all developmental stages. No survivors were found among 106,204, 96,168, and 9180 individuals of Z. tau in oranges treated at 1.75 °C for 23 d, 2.34 °C for 25 d, and 1.8 °C for 22 d, respectively. These results support for the application of the 22-day treatment at ≤1.67 °C as an additional safety measure. Such a measure mitigates the risk of introduction and establishment of Z. tau through imported citrus. However, for other susceptible hosts of Z. tau, the cold treatment schedules against Z. tau required to achieve quarantine security with larval endpoint would need to be 23 d at 1.75 °C or 25 d at 2.34 °C. These results also indicated that Z. tau exhibits the highest cold tolerance among the other tephritid species for which cold treatment have been reported. Full article

(This article belongs to the Section Insect Pest and Vector Management)

► Show Figures

Figure 1

14 pages, 4402 KB

Open AccessArticle

Methylene Blue Alleviates Thiamethoxam-Induced Toxicity in Honeybee Larvae by Activating Dihydrolipoyl Dehydrogenase

by Xiao-Shi He, Jia-Wei Huang, Chang-Hao Chu, Qi-Bao He, Min Liao, Lin-Sheng Yu, Ping-Li Dai, Yong Huang and Hai-Qun Cao

Insects 2026, 17(3), 334; https://doi.org/10.3390/insects17030334 - 19 Mar 2026

Viewed by 550

Abstract

The extensive utilization of TMX, a substance characterized by its high toxicity towards honeybees, has exerted a deleterious influence on the employment of neonicotinoid insecticides and the proliferation of bee colonies. However, there is a lack of effective solutions to mitigate the toxicological [...] Read more.

The extensive utilization of TMX, a substance characterized by its high toxicity towards honeybees, has exerted a deleterious influence on the employment of neonicotinoid insecticides and the proliferation of bee colonies. However, there is a lack of effective solutions to mitigate the toxicological impact of neonicotinoid insecticides on bees. The present study proposes a method of using MB to alleviate TMX poisoning in honeybee (Apis mellifera ligustica) larvae. The results demonstrated that when bee larvae ingested MB at a concentration of 0.32 mg·L⁻¹, the mortality rate of larvae could be reduced from 47.2% to 25.0%. Transcriptome analysis identified the honeybee dihydrolipoyl dehydrogenase (AmDld) gene as one of the main genes involved in the function of MB. AmDld was highly expressed in larval hemolymph. Its expression levels and enzymatic content were suppressed by either TMX or MB alone but restored by the TMX+MB combination. RNAi-mediated knockdown of AmDld decreased AmDld content and increased larval mortality under the TMX+MB co-treatment from 25.0% to 40.6%. This indicated that the TMX+MB combination rescued AmDld levels, thereby alleviating TMX toxicity to bee larvae. The present study has demonstrated that the ingestion of MB by honeybee larvae has the capacity to reduce the toxicity of TMX, a toxic substance, through the action of the AmDld gene. This provides a novel approach to mitigating pesticide poisoning in bees. Full article

(This article belongs to the Special Issue Honeybee and Other Pollinators: Physiology and Biochemistry Across Environmental Conditions)

► Show Figures

Graphical abstract

5 pages, 156 KB

Open AccessEditorial

RNAi in Insect Physiology: Unlocking Mechanisms and Pioneering Sustainable Pest Control

by Jisheng Liu and Luc Swevers

Insects 2026, 17(3), 333; https://doi.org/10.3390/insects17030333 - 19 Mar 2026

Viewed by 677

Abstract

The advent of RNA interference (RNAi) in 1998, marked by the discovery of gene silencing triggered by double-stranded RNA (dsRNA) in nematodes, opened a transformative chapter in molecular biology [...] Full article

(This article belongs to the Special Issue RNAi in Insect Physiology)

16 pages, 506 KB

Open AccessArticle

Comparative Assessment of the Potential of Xylocoris flavipes (Hemiptera: Anthocoridae) and Two Cheyletus spp. (Trombidiformes: Cheyletidae) for Managing Liposcelis decolor (Psocodea: Liposcelididae)

by Augustine Bosomtwe, James Danso, George Opit, Brad Kard, Kristopher Giles and Carla Goad

Insects 2026, 17(3), 332; https://doi.org/10.3390/insects17030332 - 18 Mar 2026

Viewed by 485

Abstract

Psocids are difficult to manage using insecticides, hence the need for alternatives including biological control. Evaluation of data from two separate studies was conducted. One study investigated the potential of Cheyletus eruditus (Shrank) (Trombidiformes: Cheyletidae) and Cheyletus malaccensis Oudemans to manage Liposcelis decolor [...] Read more.

Psocids are difficult to manage using insecticides, hence the need for alternatives including biological control. Evaluation of data from two separate studies was conducted. One study investigated the potential of Cheyletus eruditus (Shrank) (Trombidiformes: Cheyletidae) and Cheyletus malaccensis Oudemans to manage Liposcelis decolor (Pearman) (Psocodea: Liposcelididae), whereas the other investigated the potential of Xylocoris flavipes (Reuter) (Hemiptera: Anthocoridae) to do the same. Temperature and relative humidity conditions were similar in both studies. However, the five predator–prey (P-P) ratios for the mites (0:20, 1:20, 2:20, 4:20 and 10:20) were different from those of X. flavipes (0:240, 1:240, 2:240, 3:240 and 5:240). The three predators demonstrated significant prey suppression; however, the level of control by X. flavipes was higher compared to the mites. At optimal prey conditions of 32 °C and 75% RH, all predators maintained high suppression. Temperature significantly influenced progeny production, with high reproduction observed at 20 and 24 °C for the Cheyletus spp. and at 28 and 32 °C for X. flavipes. Relative humidity of 63% was detrimental to Cheyletus spp. progeny production. While the results from this evaluation for the purpose of comparison should be interpreted cautiously, the different performances of the predators provide valuable insights for biological control of stored-product psocids. Full article

(This article belongs to the Section Insect Physiology, Reproduction and Development)

► Show Figures

Figure 1

17 pages, 13668 KB

Open AccessArticle

Insecticide Resistance Mutations, Enzymatic Activity, and Pathogen Infection in Culex quinquefasciatus from Haiti

by Primrose Tanachaiwiwat, Neil D. Sanscrainte, Bernard A. Okech and Alden S. Estep

Insects 2026, 17(3), 331; https://doi.org/10.3390/insects17030331 - 18 Mar 2026

Viewed by 671

Abstract

Haiti is a Caribbean country of about 11 million people with a high burden of mosquito-transmitted disease and limited vector control, thereby making effective operational mosquito control of high importance. Previous studies have examined vector-borne disease burden and insecticide resistance markers in Haitian [...] Read more.

Haiti is a Caribbean country of about 11 million people with a high burden of mosquito-transmitted disease and limited vector control, thereby making effective operational mosquito control of high importance. Previous studies have examined vector-borne disease burden and insecticide resistance markers in Haitian Aedes and Anopheles mosquitoes, but not Culex species. In this study, we examined collections of Culex quinquefasciatus from 12 locations in northern and southern Haiti for the presence of markers of insecticide resistance (using a variety of target-site mutations and biochemical assays) and pathogens (using a deep-sequencing microbiome workflow). The metagenomic analysis identified Wolbachia, Rhabdoviridae, and Plasmodium infections in all sample pools at relatively high levels, along with less frequent detections of other potential pathogens. Insecticide resistance marker examination identified variable frequencies of knockdown resistance and acetylcholinesterase resistance mutations, as well as variation in resistance-associated enzymatic activities in these populations. These findings indicate that insecticide resistance to pyrethroid and organophosphate insecticides is likely. Although there was variation among Culex mosquito populations and no clear activity pattern, enzymatic activity was significantly higher at the southern sites than at the northern sites. Similar findings in Cx. quinquefasciatus populations in other locations in the Americas strongly suggest that vector control with pyrethroid and organophosphate adulticides may be of limited efficacy. Full article

(This article belongs to the Section Insect Pest and Vector Management)

► Show Figures

Figure 1

15 pages, 2383 KB

Open AccessArticle

Olfactory Susceptive Difference in Gregarious and Solitary Locusts

by Weichan Cui, Dafeng Chen, Liushu Dong and Xianhui Wang

Insects 2026, 17(3), 330; https://doi.org/10.3390/insects17030330 - 18 Mar 2026

Viewed by 584

Abstract

The migratory locust, Locusta migratoria, possesses a highly specialized olfactory system that exhibits remarkable density-dependent plasticity, which plays a crucial role in the formation of large aggregations and the resulting severe crop damage. However, the mechanisms by which population density influences phase-related [...] Read more.

The migratory locust, Locusta migratoria, possesses a highly specialized olfactory system that exhibits remarkable density-dependent plasticity, which plays a crucial role in the formation of large aggregations and the resulting severe crop damage. However, the mechanisms by which population density influences phase-related plasticity in olfactory perception remain largely unexplored. Here, we conducted a comprehensive, multi-level comparison of the peripheral olfactory system between solitary and gregarious locusts. We found that solitary male locusts display the highest total number of antennal sensilla, with basiconica sensilla being the most abundant and particularly prominent in this group. At the physiological level, solitary males also displayed the greatest overall sensitivity in their electroantennogram (EAG) responses to volatile compounds highly specific to both phase and sex. At the molecular level, solitary males exhibited a significant upregulation of Or genes across all sex-phase combinations. These findings illuminate the intricate adaptation strategies of the insect peripheral olfactory system in response to environmental changes. Full article

(This article belongs to the Section Insect Physiology, Reproduction and Development)

► Show Figures

Graphical abstract

17 pages, 1013 KB

Open AccessArticle

Can Eretmocerus eremicus Assess Oviposition Sites with Varying Host Densities and Predation Risks, and Make Decisions Based on Scent Cues?

by Luis Enrique Chavarín-Gómez, Víctor Parra-Tabla, Lizette Cicero, Carla Vanessa Sánchez-Hernández, Paola Andrea Palmeros-Suárez and Ricardo Ramírez-Romero

Insects 2026, 17(3), 329; https://doi.org/10.3390/insects17030329 - 17 Mar 2026

Viewed by 604

Abstract

Parasitoids use different signals to locate their hosts, and these signals can modulate their behavioral decisions. Thus, patch selection and foraging in patches with different characteristics depend on their ability to gather and use such information efficiently. In this study, we evaluated whether [...] Read more.

Parasitoids use different signals to locate their hosts, and these signals can modulate their behavioral decisions. Thus, patch selection and foraging in patches with different characteristics depend on their ability to gather and use such information efficiently. In this study, we evaluated whether the parasitoid Eretmocerus eremicus (Hymenoptera: Aphelinidae), a natural enemy of Trialeurodes vaporariorum (Hemiptera: Aleyrodidae) on tomato plants (Solanum lycopersicum), uses scent cues to select and forage in patches that differ in host density and predation risk. Using choice bioassays in a wind tunnel under a continuous airflow, we recorded selection patch and selection time, as well as foraging parameters, including residence time, oviposition events, and attacks. Our results show that E. eremicus discriminated between sites with and without hosts using scent cues, but discrimination between patches with different host numbers was not detected under our assay conditions. It also distinguished between patches with maximum risk and those without risk, but not between subtle differences in risk. These findings suggest that E. eremicus, responded mainly to contrasting olfactory cues rather than to subtle odor differences. From an applied standpoint, our results motivate deeper investigation into how host- and predator-associated olfactory cues could fine-tune parasitoid deployment in biological control. Full article

(This article belongs to the Special Issue Diapause Regulation and Biological Control of Natural Enemy Insects: 2nd Edition)

► Show Figures

Graphical abstract

13 pages, 756 KB

Open AccessArticle

Geographic Divergence in Heat Tolerance and Cross-Generational Responses of the Invasive Mealybug Dysmicoccus neobrevipes

by Yusha Wang, Dewei Li, Huiwen Huang, Andrew G. S. Cuthbertson, Zhongshi Zhou and Zhenqiang Qin

Insects 2026, 17(3), 328; https://doi.org/10.3390/insects17030328 - 17 Mar 2026

Viewed by 521

Abstract

As a result of global climate change, insects are increasingly being exposed to extreme temperature events; yet population-level variation in heat tolerance and its underlying mechanisms remain poorly understood. In this study, we investigated thermal adaptation in four geographically distinct populations of the [...] Read more.

As a result of global climate change, insects are increasingly being exposed to extreme temperature events; yet population-level variation in heat tolerance and its underlying mechanisms remain poorly understood. In this study, we investigated thermal adaptation in four geographically distinct populations of the invasive mealybug Dysmicoccus neobrevipes from southern China. The populations were subjected to acute heat stress across a gradient of temperatures where survival, fecundity, offspring viability, and sex ratio were quantified. We found pronounced geographic divergence in upper thermal limits: populations from warmer regions (Guangdong and Hainan) exhibited better survival, more stable reproductive output, and greater tolerance in offspring compared with populations from cooler regions (Guangxi and Yunnan). Thermal responses followed a nonlinear pattern, with moderate heat often enhancing performance, while temperatures above physiological thresholds triggered abrupt declines. Under heat stress, life-history strategies differed among populations, with some exhibiting stress-induced reproductive investment and others showing vulnerability across all traits. Importantly, acute heat exposure produced cross-generational effects, highlighting that parental thermal history can influence offspring performance. These results demonstrate that population-specific climatic adaptation, nonlinear physiological limits, and life-history trade-offs jointly shape thermal tolerance. Understanding these mechanisms provides a predictive framework for anticipating invasive pest expansion under future climatic warming and informs region-specific pest management strategy development. Full article

(This article belongs to the Section Insect Physiology, Reproduction and Development)

► Show Figures

Figure 1

13 pages, 2984 KB

Open AccessArticle

Deep Learning-Based Image Classification of Pupae from 11 Lepidoptera Pest Species

by Zitao Li and Xuankun Li

Insects 2026, 17(3), 327; https://doi.org/10.3390/insects17030327 - 17 Mar 2026

Viewed by 719

Abstract

The morphological identification of lepidopteran pest pupae has long been a difficult task. To explore automated solutions, this study established a standardized, multi-angle image dataset of pupae from 11 economically important lepidopteran pests. We then systematically evaluated six deep learning models, including both [...] Read more.

The morphological identification of lepidopteran pest pupae has long been a difficult task. To explore automated solutions, this study established a standardized, multi-angle image dataset of pupae from 11 economically important lepidopteran pests. We then systematically evaluated six deep learning models, including both convolutional neural networks and Transformer architectures. The results show that all models successfully learned to distinguish the vast majority of species, with Vit-Small achieving the highest accuracy (98.71 ± 0.16%) and the highest F1-score (98.69 ± 0.20%). This confirms that pupal morphology provides sufficient discriminative visual information to support highly accurate automated identification. However, all models exhibited consistent, minor confusion among Helicoverpa armigera, Mythimna separata and Spodoptera exigua. Analysis revealed these errors originated from specific viewing angles of a limited number of specimens, underscoring the value of the multi-angle imaging protocol used in this study. This study transforms pupal identification from a traditional taxonomic difficulty into a solvable computer vision task, providing a dataset, methodological benchmarks, and a feasibility validation for developing image-based tools for pupal-stage pest surveillance. Full article

(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)

► Show Figures

Figure 1

35 pages, 1368 KB

Open AccessReview

A Review of Artificial Diets for Aphids (Hemiptera: Aphididae)

by Rongrong Gao, Qingqiu Zeng, Ming Zhu, Zhentao Ren and Kun Xue

Insects 2026, 17(3), 326; https://doi.org/10.3390/insects17030326 - 17 Mar 2026

Viewed by 851

Abstract

Aphids are among the most significant agricultural pests worldwide. Artificial diets are a critical foundation for aphid physiological and biochemical research and the development of pest control technology. However, their phloem sap-feeding habits, extraoral digestion characteristics, and host specificities pose numerous challenges to [...] Read more.

Aphids are among the most significant agricultural pests worldwide. Artificial diets are a critical foundation for aphid physiological and biochemical research and the development of pest control technology. However, their phloem sap-feeding habits, extraoral digestion characteristics, and host specificities pose numerous challenges to the development of artificial diets for aphids, including population degradation, reduced fecundity during long-term rearing, and a lack of methodological diversity in dietary formulation research. In this review, we summarize the research on artificial diets for aphids, encompassing the history of artificial rearing, rearing methods, and nutritional composition analysis of these diets. Furthermore, we discuss the optimization of diet formulations based on aphid digestive enzymes and symbiotic bacteria. We aim to synthesize successful developments of artificial diets for aphids and extend their application to diverse aphid species. Future development of artificial aphid diets should focus on matching the types and contents of nutritional elements with the digestive enzymes and gut microbes of aphids. It is necessary to develop specific artificial diets for targeted aphid populations rather than merely adopting successful formulations and experience with Myzus persicae or Acyrthosiphon pisum. In addition, automated and large-scale aphid rearing devices should be developed, and further research on population degradation during long-term aphid rearing is required to explore multifaceted solutions involving nutritional and environmental aspects. Full article

(This article belongs to the Special Issue Science of Insect Rearing Dynamics: Discovery-Based Inquiry)

► Show Figures

Figure 1

18 pages, 3009 KB

Open AccessReview

Research Trends, Hotspots and Future Perspectives of Geometric Morphometrics in Entomology: A Scientometric Review

by Yusha Tan, Zihui Zhao, Xiaojuan Yuan, Yuanqi Zhao, Di Su and Yuehua Song

Insects 2026, 17(3), 325; https://doi.org/10.3390/insects17030325 - 17 Mar 2026

Viewed by 998

Abstract

Geometric morphometrics is an important component of quantitative research on insect morphology, widely applied in taxonomy, intraspecific variation, and phylogenetic studies. However, systematic research in this field remains limited, with few comprehensive summaries of research trends, hotspots, and core theories. This study, based [...] Read more.

Geometric morphometrics is an important component of quantitative research on insect morphology, widely applied in taxonomy, intraspecific variation, and phylogenetic studies. However, systematic research in this field remains limited, with few comprehensive summaries of research trends, hotspots, and core theories. This study, based on scientometric methods, analyzed 1321 publications indexed in the Web of Science database up to 31 December 2025, and presents a meta-scientific review from a macro perspective, revealing the research trends, hotspots, and future directions in the field. The results show that: (1) annual publications exhibit overall growth, while research methods evolved from single landmark analysis to multimodal and interdisciplinary approaches; (2) scientists from Brazil, the USA, and France are major contributors, with studies spanning morphology, taxonomy, and ecology; (3) taxonomic studies centered on wing shape analysis constitutes a major research hotspot, closely related to phylogeny, allometry, and sexual dimorphism; (4) highly co-cited studies provide the main theoretical and methodological foundations for the field. Future research, building on existing hotspots, will further integrate geometric morphometrics with genomics, ecological functional data, three-dimensional geometric morphometrics, and artificial intelligence-assisted approaches to advance integrative taxonomy within interdisciplinary and data-driven frameworks. Full article

(This article belongs to the Section Other Arthropods and General Topics)

► Show Figures

Figure 1

6 pages, 177 KB

Open AccessEditorial

Editorial for the Insects Special Issue “Bee Conservation: Behavior, Health and Pollination Ecology”

by Kit S. Prendergast

Insects 2026, 17(3), 324; https://doi.org/10.3390/insects17030324 - 17 Mar 2026

Viewed by 885

Abstract

We live in a time of bee decline, with ever-increasing publications drawing attention to reductions in bee populations, pollinator deficits, and increases in threatening processes known to impact bee populations, including habitat loss, climate change, agricultural intensification, urbanization, pesticides, pathogens and introduced plants [...] Read more.

We live in a time of bee decline, with ever-increasing publications drawing attention to reductions in bee populations, pollinator deficits, and increases in threatening processes known to impact bee populations, including habitat loss, climate change, agricultural intensification, urbanization, pesticides, pathogens and introduced plants and bees [...] Full article

(This article belongs to the Special Issue Bee Conservation: Behavior, Health and Pollination Ecology)

16 pages, 1492 KB

Open AccessArticle

Effects of Trichoderma harzianum Rifai and Chaetomium cupreum L.M. Ames on Biological Parameters of Myzus persicae (Sulzer) on Capia-Type Red Pepper (Capsicum annuum L.)

by Hilmi Kara

Insects 2026, 17(3), 323; https://doi.org/10.3390/insects17030323 - 17 Mar 2026

Viewed by 766

Abstract

The green peach aphid, Myzus persicae (Sulzer), is a globally important agricultural pest whose management is increasingly challenged by widespread insecticide resistance, prompting interest in alternative and sustainable control strategies such as endophytic fungi. This study evaluated the effects of two endophytic fungi, [...] Read more.

The green peach aphid, Myzus persicae (Sulzer), is a globally important agricultural pest whose management is increasingly challenged by widespread insecticide resistance, prompting interest in alternative and sustainable control strategies such as endophytic fungi. This study evaluated the effects of two endophytic fungi, Trichoderma harzianum and Chaetomium cupreum, applied individually or as a 1:1 mixture, on the population ecology of M. persicae feeding on capia-type red pepper (Capsicum annuum L.). Aphid development, survival, and reproduction were assessed using age-stage, two-sex life table analysis. Contrary to expectations, T. harzianum significantly enhanced aphid population growth, resulting in a higher intrinsic rate of increase (r = 0.42 d⁻¹), finite rate of increase (λ = 1.52 d⁻¹), and net reproductive rate (R₀ = 87.67 offspring) compared to the Control (r = 0.32 d⁻¹, λ = 1.37 d⁻¹, R₀ = 42.90 offspring). The Mixture treatment also increased population parameters, whereas C. cupreum showed limited effects on aphid life table traits. Population projections indicated that T. harzianum treatment could produce aphid populations approximately 380 times larger than the Control after 60 days. These results suggest that T. harzianum may improve host plant quality in ways that indirectly favor M. persicae. The findings highlight the importance of evaluating plant–fungus–herbivore interactions before incorporating endophytic fungi into integrated pest management programs. Full article

(This article belongs to the Topic Advances in Integrated Pest Management: New Tools and Tactics for Pest Control)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Insects, Volume 17, Issue 3 (March 2026) – 121 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI