Previous Issue
Volume 16, January
 
 

Insects, Volume 16, Issue 2 (February 2025) – 75 articles

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.
Order results
Result details
Section
Select all
Export citation of selected articles as:
14 pages, 750 KiB  
Article
A Preliminary Study on Identifying the Predator Community of Invasive Bactericera cockerelli (Hemiptera: Triozidae) and Developing Molecular Identification Tools for Testing Field Predation
by Shovon Chandra Sarkar, Stephen Paul Milroy and Wei Xu
Insects 2025, 16(2), 179; https://doi.org/10.3390/insects16020179 (registering DOI) - 7 Feb 2025
Abstract
The tomato potato psyllid Bactericera cockerelli (Hemiptera: Triozidae) is a significant insect pest of Solanaceae. In early 2017, it was first detected in Perth, Western Australia. The objective of this work was to identify predator species of B. cockerelli occurring in fields of [...] Read more.
The tomato potato psyllid Bactericera cockerelli (Hemiptera: Triozidae) is a significant insect pest of Solanaceae. In early 2017, it was first detected in Perth, Western Australia. The objective of this work was to identify predator species of B. cockerelli occurring in fields of Solanaceae in Western Australia. Predatory insects and arachnids were sampled using sweep netting in some of the major Solanaceae-growing regions in the south-west of Western Australia in 2021 and 2022. Several laboratory feeding trials were conducted to develop PCR primers that could detect the DNA of B. cockerelli in predators that had fed on B. cockerelli rather than on alternative diets. The primers were then used to screen predators collected from the field to identify those that had been feeding on B. cockerelli. In the two years of field sampling, the predators collected represented a broad taxonomic range. The most abundant predator was green lacewing followed by ladybirds. Further, we analysed predators belonging to seven insect taxa (one Neuroptera, two Hemiptera and four Coleoptera) for the presence of B. cockerelli DNA. We found that 45% of the individual insects from all taxa that we caught were positive for B. cockerelli DNA, and Coleopteran predators showed the highest rate of positive results. This is the first report confirming predation on invasive B. cockerelli by the resident predator community in the field in Australia. Full article
(This article belongs to the Section Insect Pest and Vector Management)
14 pages, 4128 KiB  
Article
New Mitogenomes from the Genus Ablabesmyia (Diptera: Chironomidae, Tanypodiinae): Characterization and Phylogenetic Implications
by Wen-Bin Liu, Wen-Xuan Pei, Ya-Ning Tang, Jia-Xin Nie, Wei Cao, Cheng-Yan Wang and Chun-Cai Yan
Insects 2025, 16(2), 178; https://doi.org/10.3390/insects16020178 - 7 Feb 2025
Abstract
(1) Background: The insect mitogenome encodes essential genetic components and serves as an effective marker for molecular identification and phylogenetic analysis in insects due to its small size, maternal inheritance, and rapid evolution. The morphological identification of Ablabesmyia is challenging, particularly for non-experts. [...] Read more.
(1) Background: The insect mitogenome encodes essential genetic components and serves as an effective marker for molecular identification and phylogenetic analysis in insects due to its small size, maternal inheritance, and rapid evolution. The morphological identification of Ablabesmyia is challenging, particularly for non-experts. Thus, there is an increasing need for molecular data to improve classification accuracy and phylogenetic analysis. (2) Methods: Our analysis encompassed eight species of Ablabesmyia, a single species of Conchapelopia, one species of Denopelopia, and one species of Thienemannimyia, all originating from China. We then performed a comprehensive analysis of the nucleotide composition, sequence length, and evolutionary rate. (3) Results: All newly assembled mitogenomes displayed a negative GC-skew, indicating a cytosine bias, while most exhibited a positive AT-skew, reflecting an adenine and thymine abundance. All thirteen protein-coding genes (PCGs) featured the conventional start codon ATN, aligning closely with the typical mitochondrial start codon observed in insects. The evolutionary rates of these PCGs can be ordered as follows: ND2 > ATP8 > ND6 > ND4 > ND5 > ND3 > ND4L > ND1 > CYTB > COIII > ATP6 > COII > COI. (4) Conclusions: These newly sequenced mitogenomes exhibit structural features and nucleotide compositions that closely align with those of previously reported Chironomidae species, marking a significant expansion of the chironomid mitogenome database. Full article
(This article belongs to the Special Issue Aquatic Insects Biodiversity and eDNA Monitoring)
Show Figures

Figure 1

10 pages, 1375 KiB  
Article
New Attractant Lures for Sampling Conistra vaccinii L. Populations: Bisexual Lures and a Sex Attractant (Lepidoptera: Noctuidae)
by Szabolcs Szanyi, Zoltán Varga, Antal Nagy, Gábor Szőcs, Júlia Katalin Jósvai and Miklós Tóth
Insects 2025, 16(2), 177; https://doi.org/10.3390/insects16020177 - 7 Feb 2025
Viewed by 144
Abstract
The chemical ecology and host plant preferences of the different Conistra species (Lepidoptera: Noctuidae, Xylenini) are mostly unknown, even though they are essential components of the herbivorous assemblages of temperate zone forests. During field studies, (Z)-7-tetradecenyl acetate (Z7-14Ac) was identified as a sex [...] Read more.
The chemical ecology and host plant preferences of the different Conistra species (Lepidoptera: Noctuidae, Xylenini) are mostly unknown, even though they are essential components of the herbivorous assemblages of temperate zone forests. During field studies, (Z)-7-tetradecenyl acetate (Z7-14Ac) was identified as a sex attractant of Conistra vaccinii. Phenylacetaldehyde-based synthetic and iso-amyl alcohol-based semi-synthetic lures also attracted C. vaccinii, C. rubiginea, and C. rubiginosa, and in the case of C. vaccinii, they performed better than the newly identified sex attractant. The different efficiencies of the two bisexual lures probably reflected the different feeding source preferences of the species caught. The tested lures attracted both sexes and, thus, we can estimate the actual sex ratio. These traps can be used especially in applications where female samples are needed, i.e., surveys on the reproduction biology of moths (e.g., polyandry), or in surveys of population dynamics. Full article
(This article belongs to the Section Insect Pest and Vector Management)
Show Figures

Graphical abstract

17 pages, 1901 KiB  
Article
Potential of Beauveria Species Isolated from Southern Kazakhstan for Controlling Colorado Potato Beetle (Leptinotarsa decemlineata) Populations Under Arid Conditions
by Rauza Abdukerim, Meiramgul Mussina, Gaukartas Abysheva, Nagima Tumenbayeva, Bekzat Mombayeva, Assel Karabayeva, Nurgul Amangeldi and Zamzagul Amangeldikyzy
Insects 2025, 16(2), 176; https://doi.org/10.3390/insects16020176 - 7 Feb 2025
Viewed by 157
Abstract
Environmentally sound insect pest management strategies require continuous isolation and identification of effective biocontrol agents from different ecosystems. The quest for fungal isolates that are adapted to high temperatures is particularly significant, as they hold the potential to produce mycoinsecticides that are highly [...] Read more.
Environmentally sound insect pest management strategies require continuous isolation and identification of effective biocontrol agents from different ecosystems. The quest for fungal isolates that are adapted to high temperatures is particularly significant, as they hold the potential to produce mycoinsecticides that are highly effective in semiarid and arid areas. This study aimed to collect new virulent isolates of entomopathogenic fungi (EPF) from Kazakhstan that show promise for controlling Colorado potato beetle (CPB) populations under arid conditions. Local isolates could be adapted to abiotic and biotic factors in the environment in which they survive. The findings of this study should provide insights into the species of EPF that inhabit a specific arid region of Kazakhstan, examining their traits in the regional climate, soil composition, and biological diversity. Throughout 2023–2024, a series of soil samples was collected from diverse locations within the Turkestan region of southern Kazakhstan for the isolation of EPF. The isolation of EPF was conducted using susceptible larvae of Tenebrio molitor (Coleoptera: Tenebrionidae), a host that does not have specificity for particular species of EPF. Using this insect bait, 41 pure cultures of EPF were isolated from soils in the arid zone of Kazakhstan. Polymerase chain reaction analysis based on the TEF1-α locus showed that all the isolates were indistinguishable from Beauveria bassiana ARSEF 2860 species. However, analysis of the ITS locus revealed two cryptic species: B. bassiana and B. pseudobassiana. For laboratory evaluation of biological activity EPF, the second and third instars of CPB were collected from potato fields in southern Kazakhstan and placed in plastic containers. Test CPB larvae were treated with conidia suspensions at 1 × 107 spores/mL and survival was recorded daily for 3 weeks. The results of the bioassays revealed that all the new Kazakhstan isolates were pathogenic to larvae CPB and caused complete mortality by the end of the 11-day. These results showed that new isolates of EPF were highly virulent against larvae CPB. Full article
(This article belongs to the Section Insect Pest and Vector Management)
Show Figures

Graphical abstract

13 pages, 5748 KiB  
Article
Roles of Vitellogenin and Its Receptor Genes in Female Reproduction of the Cigarette Beetle, Lasioderma serricorne
by Qian Guo, Mingxun Zu, Deqian Liu, Yi Yan, Wenjia Yang and Kangkang Xu
Insects 2025, 16(2), 175; https://doi.org/10.3390/insects16020175 - 6 Feb 2025
Viewed by 274
Abstract
Vitellogenin (Vg) and the vitellogenin receptor (VgR) play essential roles in insect reproductive development. However, the functions of Vg and VgR genes in Lasioderma serricorne, an important insect pest of stored products, are unknown. We identified and characterized these two genes, designated [...] Read more.
Vitellogenin (Vg) and the vitellogenin receptor (VgR) play essential roles in insect reproductive development. However, the functions of Vg and VgR genes in Lasioderma serricorne, an important insect pest of stored products, are unknown. We identified and characterized these two genes, designated LsVg and LsVgR, in L. serricorne. The open reading frames of LsVg and LsVgR were 5232 and 5529 bp, encoding 1743 and 1842 amino acid residues, respectively. Both LsVg and LsVgR were predominantly expressed in female adults and exhibited the highest expression in ovaries. The RNAi-mediated silencing of LsVg or LsVgR significantly decreased the average length of ovarian tubes and oocytes and severely affected ovarian development. The Knockdown of LsVg or LsVgR significantly reduced the oviposition period, the number of eggs laid, and the egg hatching rate. Females injected with dsLsVg and dsLsVg + VgR were found to had decreased vitellogenin content. The co-silencing of LsVg and LsVgR had a more pronounced effect on reducing the oviposition period and female fecundity in L. serricorne. This study revealed the importance of LsVg and LsVgR in regulating female reproduction and shows their potential as targets for RNAi-based control of L. serricorne. Full article
(This article belongs to the Special Issue Arthropod Reproductive Biology)
Show Figures

Figure 1

12 pages, 715 KiB  
Article
COI Insights into Diversity and Species Delimitation of Immature Stages of Non-Biting Midges (Diptera: Chironomidae)
by Laurynas Stasiukynas, Jekaterina Havelka, Fabio Laurindo da Silva, Maria Fernanda Torres Jimenez, Sigitas Podėnas and Aistė Lekoveckaitė
Insects 2025, 16(2), 174; https://doi.org/10.3390/insects16020174 - 6 Feb 2025
Viewed by 180
Abstract
The diversity of non-biting midges (Chironomidae, Diptera) remains an unresolved topic, with estimates of species numbers ranging from 6000 to 15,000 according to various authors. To assess Chironomidae diversity in Lithuania, we evaluate the effectiveness of COI gene-based species delimitation methods for providing [...] Read more.
The diversity of non-biting midges (Chironomidae, Diptera) remains an unresolved topic, with estimates of species numbers ranging from 6000 to 15,000 according to various authors. To assess Chironomidae diversity in Lithuania, we evaluate the effectiveness of COI gene-based species delimitation methods for providing rapid diversity estimates. Nevertheless, differences between tree-based and distance-based approaches can result in varying group classifications, which may cause species numbers to be overestimated or underestimated. For our study, we analyzed a dataset of 109 specimens sampled from six Lithuanian streams. By applying multiple methods, such as Assemble Species by Automatic Partitioning (ASAP), Automatic Barcode Gap Discovery (ABGD), the generalized mixed Yule-coalescent (GMYC) model, and the Bayesian implementation of the Poisson Tree Processes (bPTP) model, we found that species estimates ranged from 28 to 58. Among these methods, ASAP proved to be the most effective for our dataset, identifying 58 putative species. These results reinforce our assumption that the current understanding of Chironomidae species diversity is incomplete. Full article
(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)
Show Figures

Figure 1

18 pages, 14017 KiB  
Article
Structure and Ultrastructure of Three Oak Leaf Galls: Cynips quercusfolii L., Neuroterus numismalis Geoffroy and Cynips longiventris Hartig
by Leszek S. Jankiewicz, Marzenna Guzicka and Agnieszka Marasek-Ciołakowska
Insects 2025, 16(2), 173; https://doi.org/10.3390/insects16020173 - 6 Feb 2025
Viewed by 476
Abstract
The structural and ultrastructural characteristics of galls induced by three species of insects parasitizing on oak leaves (Quercus robur L.) were examined utilizing light and fluorescent microscopes, as well as scanning and transmission electron microscopes. The tissues of the investigated galls exhibited [...] Read more.
The structural and ultrastructural characteristics of galls induced by three species of insects parasitizing on oak leaves (Quercus robur L.) were examined utilizing light and fluorescent microscopes, as well as scanning and transmission electron microscopes. The tissues of the investigated galls exhibited marked differences from those of a typical oak leaf. In the Cynips quercusfolii L. gall, the larval chamber in its final stage was formed from the remnants of dead cells that remained after larval feeding on the gall nutritive tissue. The cells of the gall nutritive tissue and the cells of the gall parenchyma exhibited diametrical differences: the former contained dense cytoplasm and had large nuclei and nucleoli, whereas the latter displayed sparse cytoplasm, prominent vacuoles, and very small nuclei. The region of coalescence between the gall stalk and leaf tissues has been described. In Neuroterus numismalis Geoffroy gall, the early developmental phases have been described in detail. The external gall tissues resembled periderm, whereas periderm does not normally occur in leaves. In the cytoplasm of Cynips longiventris Hartig gall, different bodies were found, including organized smooth endoplasmic reticulum; however, not all of the observed structures were definitively classified. Full article
(This article belongs to the Special Issue Plant Manipulation by Insects: Galls, Green Islands, and More)
Show Figures

Graphical abstract

19 pages, 3989 KiB  
Article
Factors Impacting the Use of an Allelochemical Lure in Pome Fruit for Cydia pomonella (L.) Monitoring
by Alan Lee Knight, Michele Preti and Esteban Basoalto
Insects 2025, 16(2), 172; https://doi.org/10.3390/insects16020172 - 6 Feb 2025
Viewed by 272
Abstract
A four-component blend comprising pear ester, DMNT, linalool oxide, and acetic acid (CM4K) was identified as a potent allelochemical lure for both sexes of codling moth (CM), Cydia pomonella (L.). Studies conducted from 2020 to 2022 in Washington State (USA) examined factors which [...] Read more.
A four-component blend comprising pear ester, DMNT, linalool oxide, and acetic acid (CM4K) was identified as a potent allelochemical lure for both sexes of codling moth (CM), Cydia pomonella (L.). Studies conducted from 2020 to 2022 in Washington State (USA) examined factors which could impact the lure’s relative performance. The CM4K lure was effective across a range of mating disruption programs and was equally attractive in monitoring wild and sterile CM. The lure remained attractive for at least 10 weeks. Total catch in traps baited with the CM4K was significantly less impacted than a sex pheromone lure located near mating disruption dispensers and female catches were largely unaffected. Traps with the CM4K lure caught significantly more females and fewer males when placed near clusters of fruits in a trellised orchard. Two factors were found to significantly impact the relative performance of the CM4K to sex pheromone lures: the CM4K lure was only equivalent to sex pheromone lures in pear MD orchards, and apple and pear orchards with vigorous weed growth. This is the first report of a monitoring lure for a tortricid moth being negatively impacted by the background odor of non-host weed species present within an orchard. Full article
Show Figures

Figure 1

18 pages, 1587 KiB  
Article
Assessment of Scalable Fractionation Methodologies to Produce Concentrated Lauric Acid from Black Soldier Fly (Hermetia illucens) Larvae Fat
by Luis Vázquez, Carlota Reyero, Raúl Hurtado-Ribeira, David Villanueva-Bermejo, Alejandro Belinchón, José Palomar, Tiziana Fornari and Diana Martín
Insects 2025, 16(2), 171; https://doi.org/10.3390/insects16020171 - 6 Feb 2025
Viewed by 367
Abstract
In the present study, different methodologies with potential scalability and environmental friendliness, such as winterization, supercritical fluid extraction, and multistage distillation, were evaluated for lauric acid concentration. In all cases, to facilitate fractionation, the transformation of triacylglycerols into free fatty acids or fatty [...] Read more.
In the present study, different methodologies with potential scalability and environmental friendliness, such as winterization, supercritical fluid extraction, and multistage distillation, were evaluated for lauric acid concentration. In all cases, to facilitate fractionation, the transformation of triacylglycerols into free fatty acids or fatty acid ethyl esters was required as a previous step. For the winterization experimental assays, the amount and type of solvent was studied, resulting in a product containing ~65% lauric acid with a recovery of ~81% using a 1:10 oil-to-solvent ratio with hexane. On the other hand, the experimental extraction with supercritical carbon dioxide in a counter current packed column at 55 °C, 115 bar, and 70 g CO2/min, resulted in a product composed of ~80% lauric acid as ethyl ester with a recovery of ~85%. Finally, flash and multistage distillation were analysed using process simulation (Aspen Plus V14), demonstrating that this methodology can achieve 80% recovery with high purity (lauric acid: 96.7%; ethyl laurate: 97.4%), but a high vacuum is required to prevent thermal degradation of the product (lauric acid: 0.2 mbar; ethyl laurate: 1.1 mbar). Overall, the employed methodologies proved highly efficient in concentrating lauric acid, yielding a product of commercial interest and high added value. Full article
(This article belongs to the Section Role of Insects in Human Society)
Show Figures

Figure 1

16 pages, 3662 KiB  
Article
Programmable LED Array for Evaluating Artificial Light Sources to Improve Insect Trapping
by Mohsen Paryavi, Keith Weiser, Michael Melzer, Damon Crook, Chandrika Ramadugu and Daniel M. Jenkins
Insects 2025, 16(2), 170; https://doi.org/10.3390/insects16020170 - 6 Feb 2025
Viewed by 336
Abstract
We developed a programmable LED array to evaluate different wavelength illumination (UV, blue, green, yellow, amber, and red) and modulation schemes to improve catch rates in insect traps. The device can communicate through Bluetooth® with a simple Android app to update the [...] Read more.
We developed a programmable LED array to evaluate different wavelength illumination (UV, blue, green, yellow, amber, and red) and modulation schemes to improve catch rates in insect traps. The device can communicate through Bluetooth® with a simple Android app to update the operational settings to facilitate field experiments, including which LEDs to operate, when to operate (always, night only, or predefined intervals after sunset and/or before sunrise), and to change the LED intensities/modulation during operation. We used the devices to evaluate different wavelengths to improve catches in traps for coconut rhinoceros beetle (CRB; Oryctes rhinoceros Linnaeus) in the field, as well as to evaluate lighting preferences of Asian citrus psyllid (ACP; Diaphorina citri Kuwayama). In both cases, insects were most strongly attracted to constant UV illumination. However, CRB avoided traps with any “visible” wavelength LEDs placed in panels of traps, while ACP was moderately attracted to blue, yellow, and amber. For CRB, UV illumination of cups at the bottom of panel traps reduced catch rates compared to UV illumination higher in the panels of traps, consistent with observations of dorsal orientation towards light observed by other researchers in nocturnal beetles and moths. Finally, we provide some hardware design recommendations to improve the energy efficiency of similar devices for more widespread deployment in insect traps and for controlling the LEDs to evaluate the effects of intensity and modulation with minimal pulsing, which our observations suggest may result in insects avoiding traps. Full article
(This article belongs to the Collection Biocontrol and Behavioral Approaches to Manage Invasive Insects)
Show Figures

Figure 1

14 pages, 3258 KiB  
Article
New Records of Phenacoccus solenopsis Natural Enemies in Europe and Taxonomic Additions on Anagyrus matritensis
by Michele Ricupero, Emanuele Porcu, Agatino Russo, Lucia Zappalà and Gaetano Siscaro
Insects 2025, 16(2), 169; https://doi.org/10.3390/insects16020169 - 5 Feb 2025
Viewed by 408
Abstract
The cotton mealybug Phenacoccus solenopsis (Hemiptera: Pseudococcidae) is a polyphagous invasive species native to America and considered one of the major cotton pests in Asia. It is currently threatening horticultural and ornamental protected crops in Mediterranean countries. Due to ecological and environmental concerns, [...] Read more.
The cotton mealybug Phenacoccus solenopsis (Hemiptera: Pseudococcidae) is a polyphagous invasive species native to America and considered one of the major cotton pests in Asia. It is currently threatening horticultural and ornamental protected crops in Mediterranean countries. Due to ecological and environmental concerns, the conventional chemical control of P. solenopsis in new areas of introduction is being replaced by exploring the potential of indigenous natural enemies as a sustainable biological control tool. After P. solenopsis introduction in Sicily (Italy), field surveys were conducted on native natural enemies attacking the mealybug to select promising biocontrol agents for field applications. For the first time, Aenasius arizonensis (Hymenoptera: Encyrtidae) was reported in Europe, and the native Anagyrus matritensis (Hymenoptera: Encyrtidae) was recorded in association with P. solenopsis. The two parasitoid species were identified by morphological features and molecularly using a portion of the mitochondrial cytochrome oxidase subunit I (mtCOI) gene. Because of missing information, additional morphological features were provided for the morphological identification of A. matritensis. In addition, the generalist predators Cryptolaemus montrouzieri, Hippodamia variegata and Parexochomus nigripennis (Coleoptera: Coccinellidae) were also recorded attacking the invasive mealybug. Full article
(This article belongs to the Collection Hymenoptera: Biology, Taxonomy and Integrated Management)
Show Figures

Figure 1

12 pages, 273 KiB  
Review
Influence of Hyperthermia Treatment on Varroa Infestation, Viral Infections, and Honey Bee Health in Beehives
by Xinjian Xu, Shujing Zhou, Jinrong Huang, Fa Geng, Xiangjie Zhu and Hossam F. Abou-Shaara
Insects 2025, 16(2), 168; https://doi.org/10.3390/insects16020168 - 5 Feb 2025
Viewed by 467
Abstract
The mite Varroa destructor is widely acknowledged as the most destructive threat to honey bee (Apis mellifera) colonies on a global scale. Varroa mite infestations in bee colonies are intricately linked with viral infections, collaboratively leading to diminished bee populations and [...] Read more.
The mite Varroa destructor is widely acknowledged as the most destructive threat to honey bee (Apis mellifera) colonies on a global scale. Varroa mite infestations in bee colonies are intricately linked with viral infections, collaboratively leading to diminished bee populations and accelerated colony losses. Extensive research has firmly established the correlation between varroa mites and viruses, underscoring the mite’s efficiency in spreading viruses among bees and colonies. The effective control of varroa mites is expected to result in a decrease in viral infections within bee colonies. Research suggests that thermal treatments (hyperthermia) present a viable approach to combat varroa mites, with studies demonstrating the role of heat stress in reducing viral infections in affected bees. This article examines the extant literature surrounding the utilization of hyperthermia as a potential method to ameliorate the adverse impacts of varroa mites and their associated viral infections on honey bee colonies. It also outlines the thermal characteristics of these stressors. Diverse devices can be used for subjecting colonies to hyperthermia treatment, targeting mites both within and outside of brood cells. The application of thermal treatments, typically ranging between 40 and 42 °C for 1.5–3 h, as a method to reduce varroa mites and viral infections, has shown promise. Notably, the precise effectiveness of hyperthermia treatment in comparison with alternative varroa mite control measures remains uncertain within the available literature. The potential deleterious repercussions of this control mechanism on immature and mature honey bees are evaluated. Concurrently, the detrimental implications of prolonged treatment durations on colonies are discussed. Regarding viral infections, hyperthermia treatment can impact them negatively by either reducing varroa mite infestations or by inducing the production of heat shock proteins that possess potential antiviral properties. Various factors are identified as influential on hyperthermia treatment efficacy within bee colonies, including the device type and treatment duration, necessitating further empirical investigations. Additionally, this article highlights the existing gaps in the knowledge and provides insights into the prospective directions of research concerning this control method. Full article
13 pages, 1220 KiB  
Article
An Evaluation of Spodoptera littoralis and Spodoptera exigua as Natural Prey for the Generalist Predator Chrysoperla carnea
by Agustín Garzón, Óscar Giovanni Gutiérrez-Cárdenas, Beatriz Dáder, Pilar Medina and Ángeles Adán
Insects 2025, 16(2), 167; https://doi.org/10.3390/insects16020167 - 5 Feb 2025
Viewed by 274
Abstract
Chrysoperla carnea (Stephens) is a common generalist predator in agroecosystems, frequently used for the control of soft-bodied pests in augmentative releases. Better knowledge of its interactions with secondary natural prey is necessary to optimize field biocontrol performance. This work evaluates the eggs and [...] Read more.
Chrysoperla carnea (Stephens) is a common generalist predator in agroecosystems, frequently used for the control of soft-bodied pests in augmentative releases. Better knowledge of its interactions with secondary natural prey is necessary to optimize field biocontrol performance. This work evaluates the eggs and early larvae of Spodoptera exigua (Hübner) and Spodoptera littoralis (Boisduval) as natural prey for the third larval instar of C. carnea, and the predator preferences for different prey stages under varying conditions, assessing the impact on its life cycle and reproduction, in comparison with commercial diets based on Ephestia kuehniella Zeller eggs. Prey choice results were uniform for each dual prey combination irrespective of previous predator conditions (larvae number or fasting). Chrysoperla carnea did not show preference for Ephestia or Spodoptera eggs, but preferred eggs prior to larvae of the natural prey. Diets based on the frozen eggs of natural and factitious prey species showed similar effects on the development and reproduction of predator, but when C. carnea fed on S. exigua larvae, several negative effects were assessed, such as longer preimaginal development, lower adult emergence, and a reduced fecundity. These results are helpful for improving the use of lacewings as biocontrol agents in pest control programs. Full article
(This article belongs to the Section Insect Pest and Vector Management)
Show Figures

Figure 1

15 pages, 6146 KiB  
Article
Comparative Transcriptome Analysis Reveals Expression of Defense Pathways and Specific Protease Inhibitor Genes in Solanum lycopersicum in Response to Feeding by Tuta absoluta
by Yan Zhou, Yongyi Pan, Jia Liu, Wenjia Yang and Guangmao Shen
Insects 2025, 16(2), 166; https://doi.org/10.3390/insects16020166 - 5 Feb 2025
Viewed by 248
Abstract
Understanding plant-insect interactions can help control the harm of herbivorous pests. According to transcriptome data, transcripts of Solanum lycopersicum responding to feeding by Tuta absoluta were screened for important endopeptidase inhibitors. These genes were annotated as serine-type endopeptidase inhibitors from the potato inhibitor [...] Read more.
Understanding plant-insect interactions can help control the harm of herbivorous pests. According to transcriptome data, transcripts of Solanum lycopersicum responding to feeding by Tuta absoluta were screened for important endopeptidase inhibitors. These genes were annotated as serine-type endopeptidase inhibitors from the potato inhibitor I family, potato type II proteinase inhibitor family, and soybean trypsin inhibitor (Kunitz) family. Based on the analysis of expression patterns, Solyc09g084480.2, Solyc03g020080.2, Solyc03g098760.1, and Solyc01g009020.1 were identified as key genes in the defense system of S. lycopersicum. The major endopeptidase genes such as Tabs008250, Tabs007396, and Tabs005701 in the larval stages of T. absoluta were also detected as potential targets of the plant endopeptidase inhibitors. The interaction mode between these endopeptidase and endopeptidase inhibitors was predicted based on the protein structure construction. This study aims to reveal the molecular response of S. lycopersicum to feeding by T. absoluta with high throughput sequencing and bioinformatics analysis. Full article
(This article belongs to the Section Insect Molecular Biology and Genomics)
Show Figures

Figure 1

29 pages, 5744 KiB  
Review
Using Insect Larvae and Their Microbiota for Plastic Degradation
by Isabel Vital-Vilchis and Esther Karunakaran
Insects 2025, 16(2), 165; https://doi.org/10.3390/insects16020165 - 5 Feb 2025
Viewed by 306
Abstract
Plastic pollution is one of the biggest current global threats to the environment given that petroleum-based plastic is recalcitrant and can stay in the environment for decades, even centuries, depending on the specific plastic type. Since less than 10% of all plastic made [...] Read more.
Plastic pollution is one of the biggest current global threats to the environment given that petroleum-based plastic is recalcitrant and can stay in the environment for decades, even centuries, depending on the specific plastic type. Since less than 10% of all plastic made is recycled, and the other solutions (such as incineration or landfill storage) are pollutant methods, new, environmentally friendly solutions are needed. In this regard, the latest biotechnological discovery on this topic is the capability of insect larvae to use plastic polymers as carbon feedstock. This present review describes the most relevant information on the insect larvae capable of degrading plastic, mainly Galleria mellonella (Fabricius, 1798), Tenebrio molitor (Linnaeus, 1758), and Zophobas atratus (Fabricius, 1776), and also adds new information about other less commonly studied “plastivore” insects such as termites. This review covers the literature from the very first work describing plastic degradation by larvae published in 2014 all the way to the very latest research available (till June 2024), focusing on the identification of a wide variety of plastic-degrading microorganisms isolated from larvae guts and on the understanding of the potential molecular mechanisms present for degradation to take place. It also describes the latest discoveries, which include the identification of novel enzymes from waxworm saliva. Full article
(This article belongs to the Topic Diversity of Insect-Associated Microorganisms)
Show Figures

Graphical abstract

13 pages, 1245 KiB  
Review
Establishing an IPM System for Tarnished Plant Bug (Hemiptera: Miridae) in North Carolina
by Dominic Reisig and Anders Huseth
Insects 2025, 16(2), 164; https://doi.org/10.3390/insects16020164 - 5 Feb 2025
Viewed by 290
Abstract
Prior to 2010, Lygus lineolaris Palisot de Beauvois was a minor pest in North Carolina cotton, Gossypium hirsutum L., but became one of the top pests by 2017. This insect was already a persistent pest in other US cotton-producing regions. Initial work focused [...] Read more.
Prior to 2010, Lygus lineolaris Palisot de Beauvois was a minor pest in North Carolina cotton, Gossypium hirsutum L., but became one of the top pests by 2017. This insect was already a persistent pest in other US cotton-producing regions. Initial work focused on addressing near-term management needs and documenting locally relevant ecology and population dynamics of the pest in North Carolina. Landscape factors were found that correlated with tarnished plant bug incidence. Adult numbers tended to be higher in fragmented fields (more field edges) and nymph numbers were higher near field edges. The minimum required sample for estimating tarnished plant bug populations was studied. Thresholds developed in the Midsouth were proven to be useful in a study between both southeastern Virginia and northeastern North Carolina. Furthermore, an insecticide application sequence was recommended based on efficacy trials, number of expected insecticides, and preserving beneficial insects early in the season. These were evaluated in a study investigating IPM systems approaches. Finally, new management tactics for tarnished plant bug, such as ThryvOn cotton, are being evaluated. As new management strategies and tactics are developed, they will need to be evaluated for their fit in this IPM system. Full article
(This article belongs to the Collection Hemiptera: Ecology, Physiology, and Economic Importance)
Show Figures

Figure 1

16 pages, 5957 KiB  
Article
PxDorsal Regulates the Expression of Antimicrobial Peptides and Affects the Bt Susceptibility of Plutella xylostella
by Yan Sun, Haoqi Wen, Wenrui Xue and Xiaofeng Xia
Insects 2025, 16(2), 163; https://doi.org/10.3390/insects16020163 - 5 Feb 2025
Viewed by 238
Abstract
The insect NF-κB pathway is primarily constituted by nuclear factor κB (NF-κB) and the inhibitor of κB (IκB), which plays a crucial role in the innate immune response. Dorsal and Cactus, as NF-κB and IκB factors, are important downstream regulators of the Toll [...] Read more.
The insect NF-κB pathway is primarily constituted by nuclear factor κB (NF-κB) and the inhibitor of κB (IκB), which plays a crucial role in the innate immune response. Dorsal and Cactus, as NF-κB and IκB factors, are important downstream regulators of the Toll pathway in Plutella xylostella. In this study, the PxDorsal and PxCactus genes of P. xylostella were cloned, and the molecular docking demonstrated that PxDorsal and PxCactus can interact with each other. RT-qPCR results indicated that PxDorsal and PxCactus were expressed in all stages, and the expression of PxDorsal, PxCactus, and antimicrobial peptides PxGloverin2, PxMoricin3, and PxLysozyme2 were significantly down-regulated under Bacillus thuringiensis (Bt8010) infection. Interestingly, silencing the PxDorsal gene by RNA interference (RNAi) significantly down-regulated the expression of PxGloverin2 and PxMoricin3 and increased the epidermis melanization of P. xylostella larvae fed with Bt8010. Our findings indicate that PxDorsal and PxCactus may interact with each other, and silencing PxDorsal inhibits the expression of downstream antimicrobial peptides, thereby enhance the susceptibility of P. xylostella to Bt8010. This study contributes a theoretical basis for further research on the Toll pathway of P. xylostella to pathogens and offers insights for screening effective biological control targets from the perspective of the immune system. Full article
(This article belongs to the Section Insect Pest and Vector Management)
Show Figures

Figure 1

17 pages, 790 KiB  
Review
Towards a Rational Basis for the Selection of Probiotics to Improve Silkworm Health and Performance
by Siripuk Suraporn, Jisheng Liu, Feifei Ren, Luoluo Wang, Min Feng, Olle Terenius and Luc Swevers
Insects 2025, 16(2), 162; https://doi.org/10.3390/insects16020162 - 4 Feb 2025
Viewed by 396
Abstract
Pathogenic infections of silkworms constitute the greatest threat to sericulture. An attractive approach to the improvement in silkworm health and performance comprises the use of probiotics, i.e., microorganisms that confer beneficial properties such as an increased growth rate and resistance against pathogens. While [...] Read more.
Pathogenic infections of silkworms constitute the greatest threat to sericulture. An attractive approach to the improvement in silkworm health and performance comprises the use of probiotics, i.e., microorganisms that confer beneficial properties such as an increased growth rate and resistance against pathogens. While this method has already resulted in promising results, generally, there is a lack of a rational basis for guidance on the selection of probiotics. This review attempts to organize useful information that needs to be considered for the successful application of probiotics: the constitution of the microbiota in silkworms and its origins; the interaction of the major silkworm pathogens with the microbiota; and the microorganisms that have been used so far as silkworm probiotics. Our analysis points to two major issues that seem of vital importance: (1) the absence of a “core microbiota” in silkworms which necessitates continuous supply of beneficial microorganisms according to environmental conditions and (2) the apparent negative impact that some other microorganisms can have on resistance against baculovirus infections. Recent findings have reported the beneficial effects of lactic acid bacteria (Lactobacillus sp.) when applied as probiotics in improving silkworm health and performance. Full article
(This article belongs to the Special Issue Genomics and Molecular Biology in Silkworm)
Show Figures

Figure 1

12 pages, 1441 KiB  
Article
Molecular Characterization of Trypanosoma cruzi from Triatomine Species in São Paulo State, an Area Free of Vector-Borne Chagas Disease
by Eliana Ferreira Monteiro, Rubens Antonio da Silva, Arlei Marcili and Karin Kirchgatter
Insects 2025, 16(2), 161; https://doi.org/10.3390/insects16020161 - 4 Feb 2025
Viewed by 487
Abstract
Chagas disease (ChD) is a neglected tropical disease caused by Trypanosoma cruzi, endemic in 21 countries across the Americas, with increasing cases globally. In São Paulo, Brazil, vector control has focused on Triatoma infestans, but secondary triatomine species continue to pose [...] Read more.
Chagas disease (ChD) is a neglected tropical disease caused by Trypanosoma cruzi, endemic in 21 countries across the Americas, with increasing cases globally. In São Paulo, Brazil, vector control has focused on Triatoma infestans, but secondary triatomine species continue to pose transmission risks. This study aimed to investigate the prevalence of T. cruzi in triatomine feces and characterize its genetic diversity using molecular techniques. Fecal samples were collected from 570 triatomines across 25 municipalities in São Paulo, followed by DNA extraction and PCR amplification targeting the mitochondrial cytochrome b gene and the V7V8 region of the 18S rRNA gene. The results revealed a low overall infection rate (3.2%). However, excluding the triatomines collected in palm trees, all of which were negative, we found mainly Panstrongylus megistus in residences and peridomiciles, showing the highest infection rate (65%) for T. cruzi, followed by Triatoma sordida and Rhodnius neglectus. Phylogenetic analysis confirmed that DTU TcI was the most prevalent genotype, consistent with previous findings in the region. This study highlights the importance of continued vector surveillance, as these secondary species are capable of maintaining T. cruzi transmission in both urban and rural environments, underscoring the ongoing risk of ChD resurgence in São Paulo. Full article
Show Figures

Figure 1

19 pages, 619 KiB  
Review
Sex Chromosome Dosage Compensation in Insects
by Xingcheng Xie, Yakun Zhang, Heyuan Peng and Zhongyuan Deng
Insects 2025, 16(2), 160; https://doi.org/10.3390/insects16020160 - 4 Feb 2025
Viewed by 521
Abstract
Dosage compensation (DC) is of crucial importance in balancing the sex-linked gene expression between males and females. It serves to guarantee that the proteins or other enzymatic products encoded by the sex chromosome exhibit quantitative parity between the two genders. During the evolutionary [...] Read more.
Dosage compensation (DC) is of crucial importance in balancing the sex-linked gene expression between males and females. It serves to guarantee that the proteins or other enzymatic products encoded by the sex chromosome exhibit quantitative parity between the two genders. During the evolutionary process of achieving dose compensation, insects have developed a wide variety of mechanisms. There exist two primary modes of dosage compensation mechanisms, including the up-regulation of heterogametic sex chromosomes in the heterogamety and down-regulation of homogametic sex chromosomes in the homogamety. Although extensive investigations have been conducted on dosage compensation in model insects, many questions still remain unresolved. Meanwhile, research on non-model insects is attracting increasing attention. This paper systematically summarizes the current advances in the field of insect dosage compensation with respect to its types and mechanisms. The principal insects involved in this study include the Drosophila melanogaster, Tribolium castaneum, Bombyx mori, and other lepidopteran insects. This paper analyzes the controversial issues about insect dosage compensation and also provides prospects for future research. Full article
(This article belongs to the Special Issue Research on Insect Molecular Biology)
Show Figures

Figure 1

13 pages, 1654 KiB  
Article
CYP6B Subtype Expression Fluctuates in the Great Mormon, Papilio memnon, with Changes in the Components of the Host Plants
by Miho Nakano, Takuma Sakamoto, Yoshikazu Kitano, Hidemasa Bono and Hiroko Tabunoki
Insects 2025, 16(2), 159; https://doi.org/10.3390/insects16020159 - 4 Feb 2025
Viewed by 422
Abstract
Cytochrome P-450 (CYP) is one of the metabolic enzymes which is conserved among organisms to metabolise xenobiotics. The metabolic role and transcriptomic profiles of the CYP6B subfamily have been studied in some Papilionidae insects. However, the role of CYP6Bs expressed in Rutaceae [...] Read more.
Cytochrome P-450 (CYP) is one of the metabolic enzymes which is conserved among organisms to metabolise xenobiotics. The metabolic role and transcriptomic profiles of the CYP6B subfamily have been studied in some Papilionidae insects. However, the role of CYP6Bs expressed in Rutaceae plant-fed swallowtails has yet to be fully examined. Here, the expression profile of CYP6B in the Great Mormon (Papilio memnon) larvae, which prefer Citrus plants to the Rutaceae plant, was investigated by RNA sequencing analysis and real-time quantitative PCR when feeding different kinds of Citrus plants. We found that six kinds of CYP6B subtype transcripts were expressed in the larval fat body and midgut. Then, we focused on CYP6B2, CYP6B5, and CYP6B6 transcripts and examined their mRNA expression in the larvae fed on different plants. These CYP6B mRNA expressions were changed in the larval fat body and the midgut by changing the host plants. The presence of chemicals specific to each host plant was confirmed when the host plant components were examined by database, literature, and thin-layer chromatography. Our study suggests that phytochemicals in the host plant affect CYP6B subtypes mRNA expression in P. memnon larval fat body and midgut, and CYP6B subtypes may relate to metabolise the phytochemicals in the host plants. Full article
(This article belongs to the Special Issue Women’s Special Issue Series: Insects)
Show Figures

Graphical abstract

15 pages, 1708 KiB  
Article
Oviposition Deterrents from Extracts of Eryngium foetidum Against Potato Tuber Moth Phthorimaea operculella Zeller (Lepidoptera: Gelechiidae)
by Yanfen Ma, Xinzhou Yang, Mei Wu, Yunjiao Guo, Wenxia Dong, Rui Tang and Chun Xiao
Insects 2025, 16(2), 158; https://doi.org/10.3390/insects16020158 - 4 Feb 2025
Viewed by 340
Abstract
The potato tuber moth Phthorimaea operculella is a serious boring pest of potato. An integrated ecological approach to sustainable pest management is necessary for the control of this species. This study investigated the effects of minced leaves and plant extracts of Eryngium foetidum [...] Read more.
The potato tuber moth Phthorimaea operculella is a serious boring pest of potato. An integrated ecological approach to sustainable pest management is necessary for the control of this species. This study investigated the effects of minced leaves and plant extracts of Eryngium foetidum on the oviposition behavior of PTM females. The behavioral regulatory components of PTM females in response to the extracts were determined using chemical analyses and electrophysiological tests. Individual electroantennographic detection (EAD)-active compounds and mixtures were evaluated using oviposition choice bioassays. The results indicate that minced leaves had a deterrent effect on oviposition. The extracts at low dosages had an attraction effect, while high dosages had a repellent effect on the oviposition of PTM adult females. The dominant compounds of the extracts were trans-2-dodecenal and trans-2-tridecenal and showed EAD activity. trans-2-dodecenal, trans-2-tridecenal and their mixtures showed significant oviposition-repellent effects toward the PTM. The oviposition stimulation indices (OSIs) of trans-2-dodecenal and trans-2-tridecenal were −100% and −94.03% at 10 mg/mL, respectively. The OSIs of mixtures at natural ratios of 10 mg/mL and 5 mg/mL were −95.11% and −90.96%, respectively. The results can be used for the further development of ecological control strategies for this pest species. Full article
(This article belongs to the Special Issue Advances in Chemical Ecology of Plant–Insect Interactions)
Show Figures

Figure 1

19 pages, 3428 KiB  
Article
Ultrastructure of the Eggs, Larvae, and Pupae of Hyphantria cunea (Lepidoptera: Erebidae)
by Han Xue, Xinqian Liang, Qi Xie, Liu’er Yang, Mengcheng Wan and Cuiqing Gao
Insects 2025, 16(2), 157; https://doi.org/10.3390/insects16020157 - 3 Feb 2025
Viewed by 388
Abstract
Hyphantria cunea is a widespread pest that causes significant issues in forestry and agriculture, with a far-reaching global impact. However, ultramorphological studies of H. cunea, especially in terms of ultramorphological changes, are far from in-depth. Therefore, we investigated the ultrastructure of its [...] Read more.
Hyphantria cunea is a widespread pest that causes significant issues in forestry and agriculture, with a far-reaching global impact. However, ultramorphological studies of H. cunea, especially in terms of ultramorphological changes, are far from in-depth. Therefore, we investigated the ultrastructure of its eggs, larvae, and pupae using scanning electron microscopy, focusing on ultrastructural changes in larvae across different instars. The eggs have rough surfaces, and the micropylar region consists of rosette cells. The larval head chaetotaxy is symmetrically arranged, and there are three types of sensilla on the antennae and mouthparts. The abdominal and anal prolegs feature a uniordinal heteroideus midband of crochets. The pupal abdomen has ten segments; in females, the genital slit (Fgs) is located at the anterior edge of abdominal segment VIII, while in males, the genital slit (Mgs) is situated in the middle of abdominal segment IX. First-instar larvae exhibit only primary setae, and secondary setae emerge in the second instar. As the larvae mature, the head, thoracic legs, and abdominal and anal prolegs all become larger overall. The surface of the verrucae is initially smooth, with microtrichia appearing from the fourth instar onwards, and the setae on the verrucae gradually increase in size. These findings provide additional features for larval species identification and contribute to the morphological study of H. cunea. Full article
(This article belongs to the Section Insect Pest and Vector Management)
Show Figures

Figure 1

15 pages, 2947 KiB  
Article
Neem and Gliricidia Plant Leaf Extracts Improve Yield and Quality of Leaf Mustard by Managing Insect Pests’ Abundance Without Harming Beneficial Insects and Some Sensory Attributes
by Rowland Maganizo Kamanga, Salifu Bhikha, Felix Dalitso Kamala, Vincent Mgoli Mwale, Yolice Tembo and Patrick Alois Ndakidemi
Insects 2025, 16(2), 156; https://doi.org/10.3390/insects16020156 - 3 Feb 2025
Viewed by 466
Abstract
Production and consumption of vegetable crops has seen a sharp increase in the recent past owing to an increasing recognition of their nutraceutical benefits. In tandem, there has been unwarranted application of agrochemicals such as insecticides to enhance productivity and vegetable quality, at [...] Read more.
Production and consumption of vegetable crops has seen a sharp increase in the recent past owing to an increasing recognition of their nutraceutical benefits. In tandem, there has been unwarranted application of agrochemicals such as insecticides to enhance productivity and vegetable quality, at the cost of human health, and fundamental environmental and ecosystem functions and services. This study was conducted to evaluate the efficacy of neem and gliricidia botanical extracts in managing harmful insect pest populations in leaf mustard. Our results report that neem and gliricidia plant extracts enhance the yield and quality of leaf mustard by reducing the prevalence and feeding activity of harmful insect pests in a manner similar to synthetic insecticides. Some of the key insect pests reduced were Lipaphis erysimi, Pieris oleracea, Phyllotreta Cruciferae, Melanoplus sanguinipes, and Murgantia histrionica. However, compared to synthetic insecticides, neem and gliricidia plant extracts were able to preserve beneficial insects such as the Coccinellidae spp., Trichogramma minutum, Araneae spp., Lepidoptera spp., and Blattodea spp. Furthermore, plant extracts did not significantly alter sensory attributes, especially taste and odor, whereas the visual appearance of leaf mustard was greater in plants sprayed with neem and synthetic insecticides. Physiologically, plant extracts were also able to significantly lower leaf membrane damage as shown through the electrolyte leakage assay. Therefore, these plant extracts represent promising pesticidal plant materials and botanically active substances that can be leveraged to develop environmentally friendly commercial pest management products. Full article
(This article belongs to the Section Insect Pest and Vector Management)
Show Figures

Figure 1

15 pages, 6174 KiB  
Article
Impact of Temperature Variation on the Biological Traits and Lifecycle of Spodoptera exigua (Lepidoptera: Noctuidae): A Meta-Analysis Approach
by Honghua Zhang, Danping Xu, Xingqi Deng, Zhiqian Liu, Zhipeng He, Junhao Wu and Zhihang Zhuo
Insects 2025, 16(2), 155; https://doi.org/10.3390/insects16020155 - 3 Feb 2025
Viewed by 344
Abstract
Spodoptera exigua is a pest of considerable economic importance; however, detailed research into its ecological adaptability in newly invaded habitats is limited. This research performed a comprehensive analysis of the life history characteristics of S. exigua under varying temperature, photoperiod, and humidity conditions. [...] Read more.
Spodoptera exigua is a pest of considerable economic importance; however, detailed research into its ecological adaptability in newly invaded habitats is limited. This research performed a comprehensive analysis of the life history characteristics of S. exigua under varying temperature, photoperiod, and humidity conditions. A total of 264 studies that met the inclusion criteria were included in the analysis, and the data were examined using random-effects model, fixed-effects model, and meta-regression analysis techniques. The findings reveal that when temperatures exceed 20 °C, several biological parameters of S. exigua significantly increase, with the highest biological activity observed at 33 °C. As temperature rises, the duration of each developmental phase significantly decreases, accompanied by a reduction in the average number of eggs produced by females and a shorter pre-oviposition period. In addition, the pupal development period is shortened, resulting in a longer adult lifespan. By considering environmental variables such as temperature, photoperiod, and relative humidity, we identified the optimal conditions for the survival of each developmental stage of S. exigua. These results provide a foundation for predicting the population dynamics of this pest and contribute to the development of more effective pest control strategies. Full article
(This article belongs to the Special Issue Corn Insect Pests: From Biology to Control Technology)
Show Figures

Figure 1

15 pages, 5461 KiB  
Article
Identification of Fatty Acid Synthase in Arma chinensis and Its Expression Profiles in Response to Starvation
by Le Ma, Hongmei Cheng, Changjin Lin, Luyao Fu, Dianyu Liu, Yu Chen, Zhihan Su, Xiaoyu Yan, Wenyan Xu, Xiaolin Dong and Chenxi Liu
Insects 2025, 16(2), 154; https://doi.org/10.3390/insects16020154 - 3 Feb 2025
Viewed by 365
Abstract
Fatty acids are the main form of energy production and storage in insects, and fatty acid synthase (FAS) plays a major role in this process. Arma chinensis is a natural enemy used in China to control agricultural pests. While its whole genome has [...] Read more.
Fatty acids are the main form of energy production and storage in insects, and fatty acid synthase (FAS) plays a major role in this process. Arma chinensis is a natural enemy used in China to control agricultural pests. While its whole genome has been assembled, its FAS genes remain undescribed. Herein, we aim to identify the FAS genes of A. chinensis and explore their expression during starvation. Phylogenetic analysis identified nine FAS genes (ArmaFas1ArmaFas9). During the predatory developmental stages, ArmaFas9 expression gradually increased from the 2nd to the 4th instar, peaking at the 5th instar and plateauing at the adult stage. Female adults exhibited the highest expression of ArmaFas9 in their fat body and the lowest expression in their salivary glands, whereas male adults demonstrated the opposite pattern. ArmaFas9 expression was negatively correlated with starvation duration. Compared to the controls, starved adult females exhibited a downward expression trend, whereas starved adult males demonstrated an initial increase, followed by a downward trend after 7 days. Starvation and refeeding increased ArmaFas9 expression. These results demonstrate the important role of ArmaFas9 in A. chinensis growth and development, providing a basis for further studies on lipid synthesis in predatory bugs. Full article
(This article belongs to the Section Insect Molecular Biology and Genomics)
Show Figures

Figure 1

14 pages, 1972 KiB  
Article
Methyl Jasmonate Enhances the Resistance of Populus alba var. pyramidalis Against Anoplophora glabripennis (Coleoptera: Cerambycidae)
by Pengpeng Shao, Jiayu Luo, Rui Zhang, Jianfeng Liu, Dandan Cao, Zhi Su and Jianrong Wei
Insects 2025, 16(2), 153; https://doi.org/10.3390/insects16020153 - 3 Feb 2025
Viewed by 349
Abstract
Populus alba var. pyramidalis (PaP) is a very important and main planted tree species in northwestern China. However, it has been threatened by Asian longhorned beetle Anoplophora glabripennis (ALB) infestation. A feasible way to protect PaP is by improving its own insect resistance [...] Read more.
Populus alba var. pyramidalis (PaP) is a very important and main planted tree species in northwestern China. However, it has been threatened by Asian longhorned beetle Anoplophora glabripennis (ALB) infestation. A feasible way to protect PaP is by improving its own insect resistance ability. In order to achieve this goal, we first checked whether ALB could induce the defense system of PaP by comparing the ALB-attracted volatiles of PaP before and after ALB infestation through the collection and identification of volatiles by gas chromatography–mass spectrometry (GC-MS). We found that attractant volatiles (Z)-3-hexenol (Z3H) and (Z)-3-hexen-1-yl acetate (Z3HA) decreased by 72.99% and 74.53% after ALB infestation, respectively. Then, the contents of the plant hormones salicylic acid (SA), jasmonic acid (JA), methyl salicylate (MeSA), and methyl jasmonate (MeJA) and the defense substances hydrogen peroxide (H2O2), peroxidase (POD), and total superoxide dismutase (T-SOD) in the phloem of PaP were determined before and after ALB infestation by high-performance liquid chromatography–mass spectrometry (HPLC-MS) and a manufacturer’s kit, respectively. The results showed that the quantities of SA decreased, but JA and MeJA increased by 2.1 times and 3.02 times, respectively, and the increase in H2O2 and POD was also significant. Therefore, we hypothesized that MeJA might be closely related to the induced ALB resistance of PaP. Further exogenous spraying of MeJA on PaP showed that the feeding and oviposition of ALB adults were significantly decreased on PaP, confirming that MeJA could improve PaP’s resistance against ALB. The concentration effect showed that 10−4 mol/L of MeJA treatment induced the strongest results. Our results clearly demonstrated the response of a poplar species to a wood borer infestation and provide an alternative method to protect PaP in the future. Full article
(This article belongs to the Section Insect Pest and Vector Management)
Show Figures

Figure 1

19 pages, 9936 KiB  
Article
Identification of Candidate Olfactory Genes in the Antennal Transcriptome of Loxostege sticticalis Trapped by Three Different Sex Pheromone Blends
by Mengke Zhang, Sumei Zhao, Zhiping Xue, Jiaying Sun, Jiangning Hao, Fengzhi Deng, Junxia Huang, Caroline Du and Yongjun Du
Insects 2025, 16(2), 152; https://doi.org/10.3390/insects16020152 - 3 Feb 2025
Viewed by 383
Abstract
Insects sense intraspecific or interspecific information about the chemical substances in the habitat through the sensitive olfactory system to carry out foraging, mating, oviposition, and other activities. The antennae serve as the primary olfactory organs in insects. The olfactory process involves the participation [...] Read more.
Insects sense intraspecific or interspecific information about the chemical substances in the habitat through the sensitive olfactory system to carry out foraging, mating, oviposition, and other activities. The antennae serve as the primary olfactory organs in insects. The olfactory process involves the participation of many proteins, such as odorant-binding proteins (OBPs) and odorant receptors (ORs), but ORs play a central role in olfactory specificity and sensitivity. The beet webworm, Loxostege sticticalis, is an omnivorous agricultural pest that endangers crops and poses a significant risk to the agricultural and animal husbandry production in northern China. In this study, Illumina sequencing was conducted on the antennal transcriptome of male L. sticticalis trapped by three different sex pheromone blends. A total of 10,320 DEGs were identified, from which 46 candidate olfactory genes were selected for further analysis. These candidate olfactory genes comprise 13 odorant receptors, 6 ionotropic receptors (IRs), 3 gustatory receptors (GRs), 12 odorant-binding proteins, and 13 chemosensory proteins (CSPs). In summary, we analyzed the antennal transcriptome of male L. sticticalis trapped by three different sex pheromone blends and identified several candidate olfactory genes. This discovery offers a foundation for further molecular-level investigations into the olfactory system of L. sticticalis. Full article
(This article belongs to the Section Insect Molecular Biology and Genomics)
Show Figures

Figure 1

23 pages, 7686 KiB  
Article
Phylogenetics and Evolutionary Dynamics of Yunnan Acrididae Grasshoppers Inferred from 17 New Mitochondrial Genomes
by Keyao Zhang, Jing Song, Junhui Lu, Lu Zhao, Weian Deng, Delong Guan and Benyong Mao
Insects 2025, 16(2), 151; https://doi.org/10.3390/insects16020151 - 3 Feb 2025
Viewed by 455
Abstract
Yunnan Province, a global biodiversity hotspot, hosts a diverse array of Acrididae grasshoppers essential for ecosystem dynamics and agriculture. To elucidate the phylogenetic relationships and evolutionary history of this group, we sequenced and analyzed complete mitochondrial genomes from 17 Acrididae species endemic to [...] Read more.
Yunnan Province, a global biodiversity hotspot, hosts a diverse array of Acrididae grasshoppers essential for ecosystem dynamics and agriculture. To elucidate the phylogenetic relationships and evolutionary history of this group, we sequenced and analyzed complete mitochondrial genomes from 17 Acrididae species endemic to Yunnan, with genome lengths ranging from 15,403 to 15,943 base pairs. These data were integrated with mitochondrial sequences from 46 additional species to construct comprehensive phylogenetic trees. The maximum-likelihood tree identified four major clades with robust support (bootstrap values > 90%), revealing significant lineage diversification during the Early Eocene (51.94 million years ago, Mya) and subsequent radiations in the Miocene (~20 Mya) and Pliocene (~5 Mya). These divergence times correlate with major geological events and climatic shifts in the region, such as the uplift of the Tibetan Plateau and the intensification of the Asian monsoon. Notably, several species within the Coptacrinae and Oxyinae subfamilies, particularly Pseudodotraulia cornuata and Spathosternum prasiniferum, were found to be polyphyletic, indicating the necessity for taxonomic revisions. Further cluster analyses of codon usage bias and genetic distance support these taxonomic revisions within Acrididae. This robust phylogenetic framework underpins conservation strategies aimed at preserving Yunnan’s rich grasshopper biodiversity and informs updates to their phylogeny. Full article
(This article belongs to the Special Issue Revival of a Prominent Taxonomy of Insects)
Show Figures

Figure 1

22 pages, 6932 KiB  
Article
A Genome-Wide Analysis of Nuclear Mitochondrial DNA Sequences (NUMTs) in Chrysomelidae Species (Coleoptera)
by Yeyan He, Siqin Ge and Hongbin Liang
Insects 2025, 16(2), 150; https://doi.org/10.3390/insects16020150 - 2 Feb 2025
Viewed by 537
Abstract
Nuclear mitochondrial DNA sequences (NUMTs) are mitochondrial DNA fragments in the nuclear genome, and their unclear distribution in Chrysomelidae species hinders the selection of accurate molecular markers for species identification and phylogenetic analysis. Our study presents a genome-wide survey of NUMTs in 32 [...] Read more.
Nuclear mitochondrial DNA sequences (NUMTs) are mitochondrial DNA fragments in the nuclear genome, and their unclear distribution in Chrysomelidae species hinders the selection of accurate molecular markers for species identification and phylogenetic analysis. Our study presents a genome-wide survey of NUMTs in 32 Chrysomelidae species. Filtering strategies based on sequence length and open reading frame (ORF) features were employed to identify mitochondrial protein-coding genes (PCGs) minimally affected by NUMTs. Phylogenetic relationships were inferred from both mitochondrial PCG datasets and a COX1 dataset containing NUMTs. Our results show that NUMTs are chromosomally specific, species-specific, and widely distributed. ATP8, COX1, ND1, and ND4 are identified as relatively reliable molecular markers. Phylogenetic analysis is influenced by NUMTs and other factors such as sequence type and saturation. A total of 66 independent COX1 gene nuclear integration events were estimated across 32 species, mostly from distinct mitochondrial lineages. These findings suggest that NUMTs reflect key evolutionary processes such as gene flow and mitochondrial lineage diversification. Their prevalence emphasizes the need for refined molecular markers in species identification and phylogenetic analysis, while also highlighting the importance of NUMTs in understanding mitochondrial DNA integration and their contribution to species’ evolutionary history. Full article
(This article belongs to the Section Insect Molecular Biology and Genomics)
Show Figures

Figure 1

Previous Issue
Back to TopTop