Phoxim, a widely used organophosphate insecticide, poses potential risks to non-target natural enemies. Hylyphantes graminicola is a dominant predatory spider in agroecosystems, yet the sublethal effects and transgenerational impacts remain poorly characterized. This study aimed to systematically evaluate the physiological, molecular, and microbial changes in H. graminicola induced by low lethal concentration of phoxim exposure across two successive generations. Laboratory bioassays determined the LC30 of phoxim to be 9.442 mg/L. Exposure at this concentration significantly reduced female longevity but increased fecundity in both F0 and F1 generations, suggesting a potential hormetic effect. Transcriptomic analysis revealed that reproduction-related genes were significantly upregulated in the F0 generation, whereas detoxification genes were markedly expressed in the F1 generation. Functional validation through RNAi confirmed that vitellogenin (Vg) and cytochrome P450 (CYP2J1) are crucial in reproduction and detoxification, respectively. Furthermore, acetylcholinesterase (AChE) was also found to be involved in regulatory phoxim exposure. Moreover, microbiome profiling demonstrated substantial shifts across generations, including decreased Wolbachia and increased Candidatus_Cardinium abundance, which may be related to the observed increase in fecundity. The results showed that a low lethal concentration of phoxim exposure can trigger complex physiological and microbial changes across generations. These findings underscore the necessity of optimizing insecticide application intervals within Integrated Pest Management (IPM) frameworks to preserve biological control provided by beneficial arthropods. © 2026 Society of Chemical Industry.

DNA methylation is an epigenetic mechanism involved in plant defense, yet its role in insect resistance remains unclear. Although herbivory remodels plant methylomes, the links between DNA methylation, resistance traits, and phytohormone signaling remain unresolved. We induced genome-wide hypomethylation in potato plants, Solanum tuberosum L., using the DNA methyltransferase inhibitor 5-azacytidine (5-azaC), and assessed their resistance to the potato tuber moth (PTM), Phthorimaea operculella Zeller. Foliar application of 100 μm 5-azaC significantly reduced global DNA methylation in leaves and compromised resistance to Phthorimaea operculella. Larvae and adults displayed stronger feeding and oviposition preferences, respectively, for 5-azaC-treated plants and larvae gained 25.9% more weight on treated than on control plants. These dual defects were associated with marked decreases in trypsin proteinase inhibitor (TPI) accumulation and emission of the anti-herbivore volatiles such as β-caryophyllene. Moreover, hypomethylated plants had substantially lower levels of jasmonic acid (JA) and transcripts of JA biosynthetic genes. Exogenous methyl jasmonate (MeJA) restored resistance to Phthorimaea operculella by reinstating TPI accumulation and β-caryophyllene emission, whereas silencing of allene oxide cyclase gene (StAOC) caused opposite phenotype. Moreover, JA modulated genome-wide DNA methylation during herbivory and Phthorimaea operculella herbivory reduced promoter methylation of JA-related genes. Disrupting DNA methylation homeostasis compromises potato defenses and is associated with reduced JA-regulated defense outputs. Our findings reveal dynamic interplay between DNA methylation and JA-mediated herbivore defense in potato. © 2026 Society of Chemical Industry.

Insect immunity plays a key role in defense against Bacillus thuringiensis (Bt). While the Toll/Toll-like receptor (TLR) pathway is conserved for innate immunity, its specific role in immune defense against Bt remains poorly characterized. Furthermore, the functional distinctions between the prototypical Toll/TLR subtypes - single cysteine cluster (scc) and multiple cysteine cluster (mcc) - have not been thoroughly investigated. Here, we identified 12 Toll and 12 Spätzle (Spz, the Toll ligand) genes in Spodoptera litura and classified them via genome-wide phylogenetic analysis. All SlTolls are under negative selection, with mccTolls experiencing stronger purifying selection. S. litura mccTolls are intronless genes densely clustered on one chromosome, while a subset of Spz genes (group 2 Spzs) are clustered on another chromosome. S. litura mccTolls possess more structural motifs with regular arrangements, analyses of protein-protein interaction and molecular docking revealed that mccTolls exhibit broader ligand-binding specificity. SlToll7-1 (an mccToll) and SlSpz7-1 (a group 2 Spz) were significantly upregulated in the larval midgut following exposure to Bt toxins, and SlToll7-1 interacted with SlSpz7-1. RNAi-mediated knockdown of either SlToll7-1 or SlSpz7-1 significantly suppressed the expression of antimicrobial peptide (AMP) genes and increased larval susceptibility to Bt. We demonstrate that the Toll7-1-Spz7-1 pathway in S. litura is critical for defense against B. thuringiensis. Our findings also provide evolutionary insights into the diversification of mcc- and scc-Tolls/TLRs. © 2026 Society of Chemical Industry.

The rapid expansion of wild pig (Sus scrofa) populations across North America, coupled with increased concern over disease transmission, has intensified the need for effective management strategies. Trapping is widely regarded as the most effective control method; however, trapping events often fail to capture entire sounders. The behavioral responses of untrapped individuals following partial sounder removal remain poorly understood, potentially undermining management efficiency. We evaluated the spatiotemporal movement responses of wild pigs that became socially isolated following trapping events. We deployed GPS collars on 18 female wild pigs from multiple sounders and quantified post-trapping movement patterns using distance from trap site, step length, persistence velocity, space covered and overlap area over a 30-day period. Movement responses were highly variable among individuals, but wild pigs travelled an average of 1.2 km from the trap, with a maximum observed distance of 6.37 km. Space-use overlap was limited, and range sizes remained relatively stable. Individuals originating from sounders with a greater proportion of females moved farther from the trap, whereas wild pigs in better body condition exhibited lower movement velocities. Socially isolated wild pigs generally remained close to trap sites following partial sounder removal and rarely dispersed from the area. This behavioral pattern suggests a predictable post-trapping window during which untrapped individuals remain spatially accessible. These findings provide critical empirical support for adaptive trapping strategies, indicating that follow-up removal efforts can be effectively concentrated near original trap locations to improve management efficiency and reduce the risk of population persistence or disease spread. © 2026 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Neonicotinoids (NEOs) are widely used insecticides in agriculture and household pest control and have raised concerns due to their potential adverse effects on pollinator populations. NEOs can be transferred to bees during pollination and subsequently accumulate in honey, making their presence in honey of particular concern, especially in China, the world's largest honey producer. In this study, NEO levels were investigated in 86 honey samples collected from different regions of China. Among the six target NEOs, dinotefuran (DIN) showed the highest detection frequency (95.35%), while clothianidin (CLO) exhibited the highest mean concentration (7.010 μg/kg). For neonicotinoid metabolites (mNEOs), 1-methyl-3-(tetrahydro-3-furylmethyl) guanidine (DIN-G) had the highest detection rate (82.56%), and 6-chloronicotinic acid (6-CNA) showed the highest average concentration (6.640 μg/kg). Regional analysis revealed significantly higher NEO contamination in honey from southern China compared with other regions. In addition, lychee honey and polyfloral honey contained higher NEO residue levels than other honey types. Health risk assessment based on hazard quotient (HQ) and hazard index (HI) indicated that dietary exposure to NEOs through honey consumption is unlikely to pose significant health risks to consumers. This study compared NEOs residues in honey from different regions and honey types and found significantly higher NEOs concentrations in honey from southern China. Health risk assessment indicated that dietary exposure to NEOs through honey consumption is unlikely to pose significant adverse effects on human health, providing a scientific basis for market regulation and future research. © 2026 Society of Chemical Industry.

Rice bakanae disease (RBD) is a seed-borne disease known for its excessive elongation of rice seedlings due to high gibberellic acid (GA) production by the causal pathogen, Fusarium fujikuroi. At present, fungicide seed treatment is the main control strategy against RBD, but F. fujikuroi has developed resistance to almost all fungicides applied in practice, namely carbendazim, prochloraz, and phenamacril. In this study, we constructed deletion mutants of four FfP450 genes involved in GA biosynthesis in F. fujikuroi, determined the role of FfP450s in growth, development, and pathogenicity of F. fujikuroi, and investigated the bio-control potential of these deletion mutants in RBD management. None of the four FfP450 genes were involved in mycelial growth or adaptation to environmental stress. However, a higher sporulation and germination but significantly decreased gibberellin A3 production were observed in the mutants. In addition, excessive rice seedling elongation was not triggered by the mutants. In co-inoculation experiments, the FfP450-2 and FfP450-4 deletion mutants were more competitive than wild-type F. fujikuroi. Treatment with these deletion mutants resulted in good protective efficacy against RBD. The FfP450 genes were involved in the development, GA production, and pathogenicity of F. fujikuroi. ∆P450-2 and ∆P450-4 showed meaningful bio-control potential against RBD. © 2026 Society of Chemical Industry.

The degradation and utilization of lignocellulose are pivotal for understanding the competitive dynamics and coexistence mechanisms underpinning complex invasions by wood-boring beetles. Despite the broad repertoire of lignocellulolytic enzymes in these insects and their gut microbiota, the collaborative mechanisms of lignocellulose breakdown remain poorly understood. In the context of a multi-species beetle invasion system, we investigated the lignocellulose degradation processes of two major pests of Pinus massoniana, Monochamus alternatus and Orthotomicus erosus, using a combination of lignocellulase activity assays, multi-omics analyses, and two-dimensional nuclear magnetic resonance (2D-NMR). Our findings revealed that the two major pests of P. massoniana exhibit distinct lignocellulose degradation strategies driven by host enzymatic specialization: M. alternatus excels in cellulose hydrolysis via robust endogenous endoglucanases, whereas O. erosus prioritizes hemicellulose breakdown. Although the gut microbiota of both species assist terminal hydrolysis by compensating for low β-glucosidase activity and partially modifying lignin via selective β-O-4 bond cleavage, host enzyme divergence underpins their primary niche differentiation. The gut microbial composition further refines nutrient partitioning, enabling coexistence. This study unveils a dual lignocellulose degradation strategy in pine-boring beetles, integrating host enzymatic specialization and microbiome-mediated bond cleavage, which provides new insights into forest pest control and sustainable biomass utilization. © 2026 Society of Chemical Industry.

The Asian citrus psyllid, Diaphorina citri, vectors Candidatus Liberibacter asiaticus (CLas) that causes citrus greening disease, which has devastated global citrus production. Current management primarily relies on the application of synthetic chemical insecticides, resulting in the evolution of resistance among D. citri populations. CLas is ingested by D. citri while feeding on infected plants and subsequently interacts with the gut epithelial surface to establish infection. To determine the functional significance of abundant gut surface proteins in D. citri during CLas uptake, we used RNA interference (RNAi) to silence nine key gut surface protein genes. Following membrane feeding on double-stranded RNAs (dsRNAs), transcript levels were reduced by 20-51% in adults and 28-50% in nymphs at 72 h, with higher knockdown efficiencies of 41-63% in adults and 30-81% in nymphs by 120 h. Some dsRNA treatments increased D. citri mortality by approximately 20% over the control treatment, and two treatments reduced honeydew production indicative of reduced feeding consistent with disrupted gut function. Silencing of several individual proteins, including alkaline phosphatase, cadherin, cluster of calcium-transporting ATPase, croquemort and monocarboxylate transporter, reduced CLas uptake in nymphs and/or adults. Silencing of abundant gut surface proteins in D. citri limited CLas uptake, establishing a functional basis for RNAi-mediated suppression of pathogen uptake. While additional studies are needed to determine specific molecular interactions, these results identify gut surface proteins as promising targets for RNAi-based interventions to reduce CLas uptake by psyllids. © 2026 Society of Chemical Industry.

Stem rot caused by Fusarium solani significantly threatens passion fruit production. However, the pathogenic mechanisms and host defenses remain unclear. We investigated hormonal dynamics, gene regulatory networks, and pathogenic factors during F. solani infection among resistant and susceptible passion fruit cultivars. The susceptible cultivar exhibited significantly higher levels of auxin (indole-3-acetic acid, IAA), salicylic acid (SA), jasmonic acid (JA), and abscisic acid (ABA), accompanied by up-regulated expression of auxin biosynthesis (AMI1, AAO1) genes. The pink module in the weighted gene co-expression network analysis correlated strongly with JA, SA, ABA, and tryptophan; hub genes included IAA-amido synthetase and WRKY transcription factors. Enrichment of cell wall-degrading enzymes strongly correlated with SA, JA, ABA and tryptophan levels. Hence, F. solani may manipulate host hormone signaling and secrete pectin lyases to facilitate infection. This study provides insights into hormone-pathogen interactions, informing strategies for breeding disease-resistant passion fruit and developing environmentally friendly control measures. © 2026 Society of Chemical Industry.

Bridged bicyclic systems, characterized by their distinctive three-dimensional topology and inherent ring strain, confer unique spatial configurations and chemical reactivity. Increasing the molecular three-dimensionality and the fraction of sp3-hybridized carbon atoms (Csp3) in lead compounds enhances drug-like behavior. In particular, the norbornene scaffold-an archetypal bridged bicyclic framework-offers significant potential for pesticide optimization by enhancing bioactivity. We designed and synthesized 54 novel stereoisomeric derivatives containing norbornene and evaluated their antifungal activity. The bioassay results showed that most of the target compounds possessed great in vitro antifungal activity against a wide range of plant pathogenic fungi. For example, half-maximal effective concentration (EC50) = 0.31 mg/L of compound Y15 against Botrytis cinerea was comparable with that of the commercially available drug dimethachlon (EC50 = 0.37 mg/L), and 150.8-fold higher than norbornene (EC50 = 46.74 mg/L). In addition Y15 showed great aquatic biosafety, with an acute toxicity half-maximal lethal concentration (LC50) > 80.0 mg/L to zebrafish 48 h (superior to dimethachlon (LC50 = 11.90 mg/L)). RNA sequencing and quantitative reverse transcription polymerase chain reaction experiments showed that compound Y15 affected a large number of differentially expressed genes related to carbohydrate metabolism, oxidoreductase activity and membrane composition, and had a relatively large number of genes involved in microbial metabolic activity and the biosynthesis of secondary metabolites. We reported a series of novel dicarboximide fungicides containing a bridging ring structure that provided a new basis for the molecular design and mechanistic study of stereoisomeric fungicides. © 2026 Society of Chemical Industry.