The evolution of insect host adaptation is a key component of insect-plant coevolution, a complex process often shaped by multiple evolutionary events. In this study, we identified two UDP-glycosyltransferase (UGT) genes, SfruUGT33T10 and SfruUGT33F32, in the fall armyworm Spodoptera frugiperda, which are essential for tolerance to benzoxazinoids (BXs), key secondary metabolites in maize. These two detoxification enzymes exhibited distinct glycosylation patterns for BXs and varying detoxification efficiencies, reflecting independent evolutionary trajectories. Evolutionary analyses revealed that SfruUGT33T10 originated independently within Noctuidae, while SfruUGT33F32 resulted from tandem duplication within the UGT33F gene family and may have undergone neofunctionalization within the Spodoptera genus. Our findings provide evidence that the evolution of these two UGT paralogs contributed to the variation in the tolerance to maize BXs among different lepidopteran species. This research underscores the significance of multiple independent evolutionary routes in host plant adaptation and offers new insights into the complex evolutionary processes underlying insect-plant interactions.

Introgression between closely related species can profoundly influence evolutionary trajectories, yet how genomic divergence interacts with introgression, especially in invasive hybridization, remains insufficiently understood. Structural variants (SVs), particularly chromosomal inversions, are key contributors to divergence and may modulate patterns of gene flow. The Asian corn borer (ACB) and European corn borer (ECB), two globally important agricultural pests, provide an excellent system to investigate these processes. We construct a graph-based pangenome from 23 high-quality genome assemblies to characterize genome-wide SVs and introgression between ACB and ECB. We identify over 216,000 SVs, most of which are associated with transposable elements and contribute to interspecific divergence. Population genomic analyses reveal widespread yet asymmetric introgression, predominantly from ACB into ECB populations in China. Introgressed regions are more prevalent in autosomes than in sex chromosomes and are enriched for genes involved in adaptive pathways. In contrast, large inversion regions on the Z chromosome exhibit strong genetic differentiation and reduced introgression, suggesting a role in maintaining species barriers. Notably, a highly divergent region containing the circadian clock gene period (per) shows signatures of selection. Functional validation using CRISPR/Cas9 demonstrates that per significantly influences diapause regulation, linking genomic divergence to adaptive phenotypic variation. Our results demonstrate that introgression and structural variation jointly shape genomic divergence in these species. While introgression facilitates the spread of adaptive variation, chromosomal inversions restrict gene flow and maintain species integrity. This study provides new insights into the evolutionary mechanisms underlying divergence, adaptation, and invasion in major agricultural pests.

Emamectin benzoate serves as a critical insecticide for controlling Spodoptera frugiperda. However, the emergence of resistance to emamectin benzoate poses a significant challenge to effective pest management, and the underlying genetic mechanisms remain poorly elucidated. This study demonstrates that resistance levels in field populations of S. frugiperda have progressively increased, with ABCB1 expression was positively associated with resistant phenotypes. Although microRNAs (miRNAs) are well-established as crucial regulators of gene expression at the post-transcriptional level, their specific involvement in modulating ABCB1 expression remains incompletely characterized. A total of 198 miRNAs were identified in S. frugiperda, among which 28 were differentially expressed between emamectin benzoate-resistant and -susceptible strains. Notably, miR-34-5p exhibited an inverse expression pattern relative to ABCB1 across both laboratory-selected resistant strain and field-derived resistant populations. Dual-luciferase reporter assays confirmed that miR-34-5p directly targets the coding sequence of ABCB1, resulting in suppression of its expression. Functional studies demonstrated that either overexpression or knockdown of miR-34-5p significantly alters the susceptibility of S. frugiperda to emamectin benzoate. Furthermore, bioinformatic analyses revealed that the miR-34-5p binding site within ABCB1 is highly conserved between S. frugiperda and Helicoverpa armigera. In vivo experiments showed that administration of miR-34-5p antagonists results in upregulation of ABCB1 and decreased susceptibility to emamectin benzoate in H. armigera. These findings provide evidence that miR-34-5p participates in the post-transcriptional regulation of ABCB1 associated with emamectin benzoate susceptibility in S. frugiperda and expand current understanding of miRNA-mediated detoxification regulation in lepidopteran insects.

BACKGROUND:In recent years, Monolepta hieroglyphica has become a destructive pest threatening food security in northeastern China, where M. hieroglyphica adults inflict substantial yield losses through feeding on young leaves, silks and sometimes on developing kernels from maize. Plant-mediated RNA interference (RNAi) has proven to be a promising tool for sustainable pest management. Thus, specific and effective RNAi target genes for M. hieroglyphica management are needed. RESULTS:Using homology-based searching of the M. hieroglyphica genome, we identified two chitin synthase genes, and named them MhCHS1 and MhCHS2, respectively. MhCHS2 was found to be expressed in the midgut of M. hieroglyphica. We found that after feeding on transgenic maize expressing MhCHS2 double-stranded RNA (dsRNA) for 2 days, the expression of MhCHS2 was significantly reduced, and the formation of peritrophic membrane was inhibited in M. hieroglyphica. Notably, after feeding on maize expressing MhCHS2 dsRNA, half of M. hieroglyphica died within 4 days, with the majority succumbing by 7 days. Maize expressing MhCHS2 dsRNA exhibited a high degree of resistance to M. hieroglyphica. CONCLUSION:These findings further validate the essential role of MhCHS2 in maintaining formation of the peritrophic membrane and ensuring organism survival in M. hieroglyphica. This study suggests that MhCHS2 might be an ideal RNAi target for pest management, and maize expressing MhCHS2 dsRNA could be a potential and effective strategy for M. hieroglyphica control. © 2026 Society of Chemical Industry.

Agricultural pests cause enormous losses in annual agricultural production. Understanding the evolutionary responses and adaptive capacity of agricultural pests under climate change is crucial for establishing sustainable and environmentally friendly agricultural pest management. In this study, we integrate climate modeling and landscape genomics to investigate the distributional dynamics of the cotton bollworm (Helicoverpa armigera) in the adaptation to local environments and resilience to future climate change. Notably, the predicted inhabitable areas with higher suitability for the cotton bollworm could be eight times larger in the coming decades. Climate change is one of the factors driving the dynamics of distribution and population differentiation of the cotton bollworm. Approximately 19,000 years ago, the cotton bollworm expanded from its ancestral African population, followed by gradual occupations of the European, Asian, Oceanian, and American continents. Furthermore, we identify seven subpopulations with high dispersal and adaptability which may have an increased risk of invasion potential. Additionally, a large number of candidate genes and SNPs linked to climatic adaptation were mapped. These findings could inform sustainable pest management strategies in the face of climate change, aiding future pest forecasting and management planning.

Genomics has revolutionized our understanding of agricultural insects by revealing the genetic basis of their adaptation, pesticide resistance, and ecological success, while also driving the development of sustainable pest management innovations. Breakthroughs across sequencing technologies, comparative genomics, and population genomics have mapped genomes, identified resistance-linked genes such as P450s, monitored invasive lineages, and tracked alleles' spread in real time. While pangenomics captures the intra-species diversity critical for resilience, epigenomics uncovers heritable noncoding mechanisms shaping phenotypic plasticity under environmental stress. Structural genomics elucidates the protein targets for novel insecticides, and museum genomics reconstructs historical adaptations by employing archival DNA. Mitochondrial genomics allows species identification and dispersal tracking. Translational genomics bridges discoveries to field applications, such as CRISPR-edited sterile insects or RNA interference (RNAi)-based methods. Nevertheless, key gaps persist: the role of noncoding regions, horizontal gene transfer in trait acquisition, and intron–exon dynamics in adaptive evolution remain underexplored. Integrating multi-omics with artificial intelligence (AI)-driven predictive approaches could forecast climate-induced pest shifts and resistance trajectories. Ethical frameworks must parallel technical advances to address gene-driven risks and equitable access. By merging cutting-edge genomics with cross-disciplinary collaboration, this field holds unparalleled potential to combat pesticide resistance, pre-empt emerging threats, and redefine pest management in an era of agricultural uncertainty.

Since its invasion in the Eastern Hemisphere, the fall armyworm (Spodoptera frugiperda) has rapidly become one of the world's most destructive invasive species. Its explosive spread and severe damage to crops have brought this originally regionally distributed pest into global focus and made it a hot topic in agricultural pest research. It has prompted a series of biological and ecological studies, including systematic research on host selection, population dynamics, insecticide resistance, and more, gradually revealing the biological foundations of the pest and enabling a more comprehensive understanding of its impact. However, to date, knowledge about the genetic properties of fall armyworm strains and the mechanisms behind its invasion and outbreaks remains incomplete and requires further investigation. This review systematically summarizes recent research progress on fall armyworm from the perspective of genomics and molecular biology, providing scientific insights and prospects for understanding strain differentiation and population evolution in this species.

BACKGROUND:The white-backed planthopper (WBPH), Sogatella furcifera (Horváth) (Homoptera: Delphacidae), is a highly migratory insect pest that poses a significant threat to rice production in East and Southeast Asia. Although considerable advances have been made in understanding its migration sources and dispersal patterns with the advent of newer molecular tools, genomic-level insights into these processes, as well as its environmental adaptation mechanisms, remain limited. RESULTS:This study conducted whole-genome resequencing of 289 WBPH individuals from China and Southeast Asian countries, including Myanmar, Laos and Vietnam, to investigate population structure, gene flow and selective signals. Our nuclear and mitochondrial genome analysis revealed minimal genetic differentiation among populations across these regions, suggesting extensive gene flow within and between geographical areas. Consistent demographic patterns across subpopulations highlighted a slight population size reduction during the Last Glacial Maximum, around 20 000-25 000 years ago. The Central China (HBJZ population, Jingzhou, Hubei Province) seems to be a transient hub, with individuals migrating in before dispersing northward across China. Composite likelihood ratio analysis identified 560 regions, encompassing 229 genes, as potential targets of selective sweeps. Kyoto Encyclopedia of Genes and Genomics and Gene Ontology enrichment analyses revealed significant enrichment in pathways associated with circadian rhythm, muscle development and function, and cellular responses to cold stress, suggesting adaptive mechanisms that enhance flight endurance and energy efficiency during migration. CONCLUSION:This study provides a comprehensive genomic resource for investigating the migratory behavior and adaptive strategies of WBPH, shedding light on the genomic basis of its evolutionary adaptation across diverse habitats and agroecosystems in Asia. © 2025 Society of Chemical Industry.

BACKGROUND:Bacillus thuringiensis (Bt) crops, which produce insecticidal proteins such as Vip3Aa and Cry toxins, have revolutionized pest management by reducing reliance on chemical pesticides. However, the evolution of resistance in target pests has prompted investigation into the underlying mechanisms. A recent study identified a mutation in the chitin synthase gene (SfCHS2) as a key factor in Vip3Aa resistance in Spodoptera frugiperda. Here, we examined the role of CHS2 in resistance in two additional lepidopteran species: Spodoptera exigua and Agrotis ipsilon. RESULTS:Using a CRISPR/Cas9 gene-editing approach, we generated CHS2 knockout strains in both species. The mutants exhibited high-level resistance to Vip3Aa, surviving the highest tested concentration (800 μg/cm2), with resistance ratios exceeding 33 333-fold in S. exigua and 11 268-fold in A. ipsilon. Additionally, knockout strains lack the peritrophic matrix (PM), whereas the resistant Sfru_R3 strain retained its PM. CONCLUSIONS:These findings further validate the essential role of the CHS2 gene-and the PM it produces-in Vip3Aa toxicity. Complete knockout confers high resistance but imposes severe fitness costs, suggesting that such alleles are unlikely to persist in natural populations. This study advances our understanding of the molecular mechanisms behind resistance to Vip3Aa and provides insights for developing effective resistance management strategies in Bt crop management. © 2025 Society of Chemical Industry.

The invasion of the fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), has posed a serious threat to maize production in Africa and Asia. Chemical insecticides and Bt maize are the main means for FAW control, but the interaction between these two measures is also unclear. In this study, the susceptibility of the field population (Ezhou) fed on Bt maize insecticidal protein and the Vip3Aa-resistant population DH-R (206-fold) to emamectin benzoate (EB) and chlorantraniliprole (CAP) was determined by the topical application method. The results showed that the susceptibility of both populations to the two insecticides increased significantly. The mechanism is attributed to the inhibition of the activities of enzymes detoxification enzymes, including carboxylesterase (CarE), glutathione S-transferase (GSTs), and multifunctional oxidase (MFO). The corrected control effects of Bt (Cry1Ab + Vip3Aa) maize combined with EB or CAP against larvae were measured by a spraying method in the laboratory and field. The results showed that the combined use of Bt (Cry1Ab + Vip3Aa) maize and EB increased the corrected control effect by 22.70

Colorectal cancer (CRC) treatment is hampered by high recurrence rates and drug resistance. Cuproptosis, a copper-induced cell death mechanism, offers a new therapeutic approach. Here, we identified a marine natural product, chagosendine C (CHC), which kills tumor cells by increasing the intracellular copper ion concentration. CHC and related metal coordination homodimer alkaloids were rapidly synthesized and purified for further pharmacological study. In vitro, CHC significantly inhibited HCT116 and RKO CRC cell growth, induced G1 phase arrest and cell death, and overcame oxaliplatin resistance. In vivo, CHC suppressed colorectal tumor growth in mice at 40 mg/kg without obvious toxic effects. Mechanistically, CHC induces cuproptosis by targeting FDX1, increasing intracellular copper ions and ROS levels in tumor cells, and leading to cell death. Thus, CHC presents a novel CRC treatment strategy, showing strong antitumor activity and potential to overcome oxaliplatin resistance with promising clinical prospects.

Hermonassa cecilia is a Lepidoptera pest primarily distributed in East Asia, belonging to the subfamily Noctuinae, which includes species that typically target and damage the underground parts of plants. However, there is limited information available on the life history and genomic resources of H. cecilia to date. In this study, we present a high-quality reference genome of H. cecilia generated using PacBio sequencing and Hi-C methods. The assembled genome size is 626.10 Mb, with a N50 of 21.00 Mb, and the contigs were mapped onto 31 chromosomes. BUSCO analysis indicated high genome completeness, with a score of 99.40%. We identified 281.45 Mb of repetitive sequences, which account for 44.21% of the genome, and annotated 22,662 protein-coding genes, 89.29% of which had functional annotations. This study represents the first assembly and annotation of the H. cecilia genome, providing a valuable resource for understanding its biological characteristics and offering significant potential for comparative genomics within the Noctuinae subfamily.

The oriental armyworm, Mythimna separata, poses a persistent challenge to agricultural pest management due to its strong migratory abilities and polyphagous feeding behavior. In this study, we present a chromosome-level genome assembly using Illumina, PacBio HiFi, and Hi-C sequencing technologies. The final assembly spans 714.5 Mb with a scaffold N50 of 22.7 Mb and a GC content of 38.8%. A total of 32 chromosomes were successfully anchored, including the Z and W sex chromosomes. BUSCO analysis indicated a genome completeness of 98.6%, and 19,879 protein-coding genes were predicted. The W chromosome, measuring 30.55 Mb with a repeat content of 68.34%, harbors 824 protein-coding genes. Furthermore, a PCR-based method confirmed W-linked sequences for female-specific sex detection via the ZW system. This enhanced genome assembly provides a valuable resource for evolutionary research on M. separata and facilitates the development of sex-regulated pest control strategies.

Gene editing technologies are playing an increasingly important role in the study of insect gene functions. Appropriate incubation humidity helps improve the hatching rate of insect eggs. However, to date, no study has evaluated the impact of humidity on the hatching rate of gene-edited eggs or the subsequent development of the larvae. Using the cotton bollworm Helicoverpa armigera (Lepidoptera: Noctuidae) as a model, we investigated the weight and hatching rate of microinjected eggs under different humidity conditions. We determined the larval development time and pupal weight and calculated the larval gene editing efficiency. The results showed that post-microinjection incubation under high humidity (RH = 95%) had a significant influence on CRISPR/Cas9 gene-edited eggs. The key research results indicate that, compared with the incubation environment with RH ≤ 80%, after 48 h of incubation under 95% RH, the hatching rate of H. armigera eggs increased by more than 27.5%, with higher egg saturation and greater egg weight; meanwhile, the larval developmental duration was shorter and the pupal weight was also greater. These results establish a humidity-regulated developmental recovery protocol for gene-edited insects, which provides theoretical and practical support for optimizing post-microinjection recovery processes in gene-edited insects.

Bacillus thuringiensis (Bt) crops, engineered to produce insecticidal proteins such as Vip3Aa and Cry toxins, have revolutionized pest management by providing a sustainable alternative to chemical pesticides. However, the development of resistance to these toxins has driven the investigation of underlying mechanisms to better understand how pests evade toxicity and to develop more effective resistance management strategies. Recently, a laboratory-selected Spodoptera frugiperda strain exhibited a high level of resistance to Vip3Aa (resistance ratio: 5562-fold), with the mutation of the chitin synthase gene, SfCHS2 , identified as a key factor. In this study, we extend these findings to additional lepidopteran species, including Spodoptera exigua and Agrotis ipsilon . Our results show that CHS2 knockout strains lack the peritrophic matrix (PM), while the resistant Sfru\_R3 strain retains its PM. Knockout of this gene in five lepidopteran species resulted in high levels resistance to Vip3Aa. Notably, homozygous knockout strains suffered significant fitness costs and had difficulty surviving on corn leaves, in contrast to the Sfru\_R3 strain, which showed no such survival issues. These findings further validate the role of the CHS2 gene in Vip3Aa resistance and highlight its potential as a target for resistance management in lepidopteran pests. This study advances our understanding of the molecular mechanisms behind resistance to Vip3Aa and supports the development of strategies to delay resistance in Bt crop management. ### Competing Interest Statement The authors have declared no competing interest. Biological Breeding-National Science and Technology Major Project, 2022ZD04021 Agricultural Science and Technology Innovation Program, CAAS-ZDRW202412 Innovation Program of Chinese Academy of Agricultural Sciences, CAAS-CSCB-202303 Shenzhen Science and Technology Program, KQTD20180411143628272 National Natural Science Foundation of China, 32202352 The Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences

Background Moths constitute the largest group within Lepidoptera and play a crucial role in natural ecosystems. However, the current high-level classification system of Lepidopteran insects necessitates systematic research supported by comprehensive data. Results In this study, we determined the complete mitochondrial genomes of 80 lepidopteran moth species, spanning 68 genera across 13 families. Through a synthesis of published data, we conducted a comparative analysis encompassing 211 moth species from 12 superfamilies. Our analysis unveiled a mitochondrial genome length range of 15,027 to 17,049 bp, with an AT content varying between 77.02% and 83.52%. While gene composition and arrangement were largely conserved, we observed tRNA rearrangement (trnS1-trnE inversion) in Zygaenidae and Gelechiidae families. Phylogenetic analyses highlighted the monophyly of 9 superfamilies, with exceptions for Tineoidea, Pyraloidea, and Drepanoidea. Divergence time estimations suggest an origin of the 12 Lepidopteran superfamilies in the mid-Cretaceous period, approximately 122.27 million years ago (95% CI: 102.43-153.23 Mya). Furthermore, we propose reclassifications to refine the taxonomic status of certain families. This includes reclassifying Gracillariidae and Thyrididae as independent from the Tineoidea and Pyraloidea superfamilies, respectively, and relocating the family Epicopeiidae to the Geometroidea superfamily from Drepanoidea. Conclusion We performed a comprehensive comparative analysis of mitochondrial genomes from 211 moth species. Using various tree-building methods and datasets, we reconstructed the higher-level phylogeny of moths across 12 superfamilies of Lepidoptera and further proposed taxonomic revisions for several groups. Our study significantly enriches the molecular dataset for moth systematics and offers new insights into the evolutionary history and phylogeny of Lepidoptera.

Background/Objectives: As crucial natural predators, hornets contribute to ecosystem function by preying on agricultural and forest pests and facilitating plant pollination. However, the predatory preference of hornets for honeybees poses a significant threat to honeybee pollination and the development of the beekeeping industry. Foraging and pollination behaviors in hornets are largely governed by a sensitive olfactory system, but their olfactory molecular mechanisms remain poorly understood. Methods: VvelCSP1 and VvelCSP4 were successfully expressed in the prokaryotic expression system and purified by Ni-NTA affinity chromatography column. Fluorescence competitive binding assays were employed to evaluate their binding affinities to volatile compounds derived from the seed elaiosome of Stemona tuberosa and honeybees. Molecular docking was further performed to analyze key residues and interaction patterns within the binding pockets. Results: Fluorescence competitive binding assays showed that both proteins prefer long-chain alkanes yet exhibit significant substrate selectivity and high ligand specificity. VvelCSP1 specifically binds to hexacosane, while VvelCSP4 specifically recognizes docosane. Molecular docking results demonstrated that the binding process between VvelCSP1, VvelCSP4 and their respective ligands is dominated by hydrophobic interactions. Conclusions: This study provides functional evidence for investigating the olfactory molecular regulation mechanisms underlying hornet-mediated seed dispersal. These findings establish a foundation for potential applications of hornets in plant propagation, biological pest control, crop pollination and ecological balance maintenance in agroforestry systems.

BACKGROUND:Matrine, the main active ingredient in Sophora flavescens and Sophorae tonkinensis radix et rhizome, is a highly effective insecticide. However, its hepatotoxicity to some extent affects its application value. This study aimed to explore the mechanism underlying matrine-induced liver injury. METHODS:The zebrafish (Danio rerio) and L02 cell model were utilized to investigate the toxic dose of matrine and its effects on liver tissue damage, liver cell morphology and activity, and expression levels of ALT and AST. Zebrafish and L02 cell samples were then collected for transcriptomic testing to further explore the possible mechanism by which matrine induced liver injury. Finally, integrated bioinformatics methods and experiments were used to elucidate the possible mechanisms behind matrine-induced liver injury. RESULTS:The result presented solid in vivo evidence of matrine-induced hepatotoxicity, supported by abnormal changes of liver morphological, disturbed liver cell structure, obvious apoptosis, as well as elevated levels of ALT and AST in zebrafish. In addition, in vitro L02 cell experiments also showed that matrine can produce significant liver cell damage effects. The integrated bioinformatics analysis results revealed that differentially expressed genes (DEGs) were substantially enriched in multiple pathways related to lipid regulation. Among which, the steroid biosynthesis was the most key signaling pathway, evidenced by the enhanced expression of eight genes, including DHCR7, SQLE, CYP51, CYP24A1, SC5D, LSS, MSMO1 and SOAT1. Furthermore, AY9944, the targeted inhibitor of DHCR7, could offset the toxic effect, as reflected by diminished liver phenotype damage, steatosis, and cholesterol accumulation caused by matrine. CONCLUSIONS:Matrine can upregulate the expression of key genes in steroid biosynthesis pathway, resulting in cholesterol accumulation and then inducing hepatotoxicity. Among them, targeted inhibition of DHCR7 gene expression can alleviate matrine-induced liver injury.