Pest Management Science最新文献

Background: The pine wood nematode Bursaphelenchus xylophilus, an invasive species, drives pine wilt disease epidemics in coniferous ecosystems. During long-term in vitro subculture, the virulence of this nematode strongly attenuated. In this study, we investigated how sustained mycophagous subculture drives adaptive shifts that reduce B. xylophilus virulence.

Results: In pathogenicity assays, the mortality of Pinus thunbergii seedlings reduced by 70% with 180-day subcultured nematodes compared to non-subcultured in vivo populations. Adult body size (25-49% decrease in length; female: from 1207 to 907 μm; male: from 1348 to 688 μm) and thrashing frequency (by 62.8%) decreased, but female-biased sex ratio increased (from 0.94:1 to 2.08:1). Integrated omics analyses identified 702 differentially expressed genes, with subcultured nematodes exhibiting up-regulation of spliceosome/ribosome biogenesis pathways and down-regulation of phytophagy-associated systems (e.g., G protein-coupled receptor activity and xenobiotic metabolism). Notably, 50 differentially expressed microRNAs target developmental and signal transduction genes, suggesting post-transcriptional regulation of adaptive traits. Metabolomics revealed consumption of defense-linked tyrosine derivatives in vivo and accumulation of growth-promoting metabolites in vitro.

Conclusion: Mycophagy-driven adaptation attenuates phytophagous traits essential for host invasion, such as chemoreception and detoxification machinery, thereby offering promising targets for RNA interference to manage pine wilt disease. © 2026 Society of Chemical Industry.

Background: There is a close relationship between habitat, food and demographic parameters of common vole populations. The current study investigates the relationship between the quality of food consumed by adult voles in different habitats and vole body size. Populations of common voles were monitored within a small region under the same weather conditions in both forest and agricultural habitats. The quality of the food consumed was determined using near-infrared spectroscopy. The indicator of food quality was the content of nitrogenous compounds. Other key variables were also considered: sex, reproduction, year and date of capture, and relative vole abundance in each plot.

Results: Food quality and body size were dependent on date and habitat. Voles from arable habitats, such as cereals, rape and alfalfa, were larger than those from less managed habitats (set-aside, clearings and forests). Differences in body size did not appear to be directly related to food quality; voles in cereals had lower food quality than voles in clearings, rape, alfalfa and set-aside. Individuals captured in 2008 were smaller than in other years, but the year of capture did not affect food quality.

Conclusion: Diet quality is a limiting factor for body growth, but body size is influenced by factors other than food nitrogen content alone. © 2026 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Background: Sorghum bicolor and Sorghum halepense can readily hybridize, creating difficulty in identification. No genetic tools exist to accurately distinguish S. bicolor, S. halepense, and their hybrids. Detecting hybridization is essential to monitor crop-to-weed introgression. This study utilizes a single nucleotide polymorphism (SNP) in the internal transcribed spacer region between S. bicolor and S. halepense. This SNP was utilized in Kompetitive allele-specific PCR (KASP) assay to identify S. bicolor, S. halepense, and their hybrids.

Results: KASP assays were successful in accurately differentiating between S. bicolor, S. halepense, and their hybrids. The KASP assay performed as well as Oxford Nanopore sequencing for measuring SNP frequency and thus is a perfect proxy for genotyping. Greenhouse crosses confirmed crop-to-weed introgression, with S. halepense being more receptive to interspecific pollen. Known and unknown samples assayed displayed misidentification in germplasm lines and significant hybrid frequency in naturally occurring biotypes. Synteny analyses revealed duplications of the ITS region in S. halepense.

Conclusion: We developed a novel KASP assay targeting a conserved SNP that accurately distinguishes between S. bicolor, S. halepense, and their hybrids. This assay was validated through Oxford Nanopore sequencing, greenhouse crosses, and diverse germplasm and natural collections. © 2026 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Background: The enhanced capacity for metabolic detoxification is a key adaptive strategy enabling insects to tolerate plant secondary metabolites (PSMs). This adaptation is largely driven by the transcriptional regulation of detoxification genes. Our previous work established the critical involvement of specific detoxification enzymes in xanthotoxin metabolism in Spodoptera litura. In the present study, we aimed to identify and characterize the transcription factors responsible for orchestrating detoxification gene expression.

Results: RNA-sequencing analysis revealed that, alongside transcription factors induced by xanthotoxin, the nuclear receptor hormone receptor-like 51 (HR51) was uniquely and consistently down-regulated in both the midgut and fat body of S. litura. To elucidate the role of HR51 in xanthotoxin detoxification, we generated HR51-knockout mutants using CRISPR/Cas9-mediated gene editing. These mutants displayed markedly enhanced tolerance to xanthotoxin, accompanied by the up-regulation of detoxification genes responsible for its metabolism. Mechanistic studies through dual-luciferase reporter assays coupled with site-directed mutagenesis demonstrated that HR51 suppressed the expression of detoxification genes through binding to the specific cis-acting element within their promoter.

Conclusion: This study uncovers a novel derepression mechanism in which suppression of the transcriptional repressor HR51 alleviates its inhibition on detoxification genes, thereby facilitating S. litura adaptation to xanthotoxin. These findings advance our understanding of insect counter-defense against PSMs and highlight HR51 as a promising molecular target for the development of innovative pest management strategies. © 2026 Society of Chemical Industry.

Background: Herbivore-induced plant volatiles (HIPVs) play multiple roles in mediating plant-arthropod species interactions. Methyl salicylate (MeSA) is a well-known HIPV given its effectiveness in attracting parasitoids and predators and its use in biological control strategies. In addition, non-crop vegetation of field margins are important habitats that harbor natural enemies but may fail to increase biological control. Volatiles like MeSA could synergistically interact with field margin vegetation and increase biological control within crops. The present study examines through a field experiment the effects of MeSA (MeSA-exposed versus control plants) and in-field location (near vegetation margins versus field center) on plant-arthropod interactions to enhance biological control of Brassicaceae pests.

Results: MeSA-exposed cabbage plants tended to have different volatile compositions than control plants, showing a slight proportional increase in 3-pentanol and the absence of hexenal in MeSA-exposed samples. Herbivore abundance was slightly lower in MeSA-exposed compared to control plants, while in-field location did not influence the second trophic level. Natural enemy abundance and parasitism rates were significantly higher in the field margins than in the center, but the opposite pattern was registered for predation. No MeSA effects were detected on third trophic level species.

Conclusion: MeSA altered plant volatile organic compound (VOC) emissions and had a slight effect on herbivores, while natural enemies responded solely to field-margin vegetation. Our study highlights the importance of conserving spontaneous vegetation to support parasitoids and underscore the need to study several functional groups and trophic levels for improving biological control. The use of VOCs, integrated with habitat management strategies, represents a complementary approach to enhance pest control. © 2026 Society of Chemical Industry.

Background: With increasing resistance to traditional fungicides and growing environmental concerns, it is crucial to develop novel succinate dehydrogenase inhibitors to enhance disease management and support sustainable agriculture.

Results: This study systematically designed and synthesized a series of nicotinohydrazides bearing a biphenyl fragment, evaluating their antifungal activity against six plant pathogenic fungi. The results demonstrated that their fungicidal spectrum significantly surpasses boscalid and carbendazim. Utilizing a palladium-catalyzed cross-coupling strategy, combined with diazotization-reduction and dehydration condensation reactions, we successfully synthesized 35 target compounds (F1-F18, G1-G17). Antifungal assays revealed that most compounds exhibited more than 80% inhibition against the tested fungi at a concentration of 20 mg/L, particularly compound F17, which showed a half-maximal effective concentrations value ranging from 0.33 to 2.77 mg/L and achieved an efficacy of 89.94% against Sclerotinia sclerotiorum on canola leaves at a concentration of 200 mg/L. Mechanistic investigations indicated that F17 exerts its antifungal effects through multiple mechanisms, including the inhibition of succinate dehydrogenase, disruption of cell membranes and induction of oxidative damage. Toxicity predictions and cytotoxicity assays assessed the safety of this series of compounds. Density functional theory and molecular electrostatic potential analyses elucidated the reasons for the high activity of F17.

Conclusion: Nicotinohydrazide derivatives exhibit a broader spectrum of antifungal activity than traditional inhibitors, and their multiple mechanisms of action provide a theoretical basis for further structural optimization and the design of novel agrochemicals. © 2026 Society of Chemical Industry.

Background: Tomato chlorosis virus (ToCV) and tomato yellow leaf curl virus (TYLCV) are two important plant viruses. Co-infection of them leads to exacerbated disease symptoms and poses a significant challenge for control. Using nanomaterials to package and deliver double-stranded RNA (dsRNA) for inducing RNA interference (RNAi) has emerged as a promising antiviral strategy in agriculture.

Results: In this study, two established nanomaterials, chitosan quaternary ammonium salt (CQAS) and aminated mesoporous silica nanoparticles (MSN@NH₂), were selected to package dsRNAs targeting the TYLCV C1 gene, the ToCV RNA-dependent RNA polymerase (RdRP) gene, or the ToCV 1a polyprotein gene, forming CQAS/dsRNA and MSN@NH₂/dsRNA nanoparticles, respectively. The results indicated that these nanoparticles enhance the stabilities of dsRNAs. The efficacy of these nanoparticles against ToCV and TYLCV infection was assessed in tobacco cv. K326, Nicotiana benthamiana, and tomato cv. Micro-Tom plants. The results showed that these nanoparticles could significantly reduce viral gene transcription levels, with inhibition rates ranging from 33.5% to 99.5% depending on the nanoparticle formulation, target virus, and host plant. For instance, in N. benthamiana under co-infection, MSN@NH2/dsRNA nanoparticles inhibited TYLCV and ToCV by 99.5% and 79.8%, respectively. These findings demonstrate that both CQAS/dsRNA and MSN@NH2/dsRNA nanoparticles are effective in controlling ToCV and TYLCV single or co-infection in plants.

Conclusion: Both CQAS and MSN@NH₂ effectively package and protect dsRNA from degradation. Our findings further support the notion that the nanoparticle-mediated RNAi is a promising strategy for virus disease management. This approach contributes to global efforts toward sustainable agriculture. © 2026 Society of Chemical Industry.

Background: Managing stored-grain pests requires new strategies to limit economic and health risks. This study analyses the sublethal effects of the natural compound carlina oxide on Prostephanus truncatus, providing new behavioural insights through a multidisciplinary approach. A fully automatic computer vision approach was developed to label two specific insect body parts, enabling the generation of an annotated dataset without manual intervention. This dataset was used to train a convolutional neural network (CNN) for pose estimation. A second dedicated CNN focused on the antennae to investigate neuroethological and sensory variations.

Results: CNN for body parts detection achieved an average precision of 0.78, recall of 0.90, and F1 score of 0.84 on the test dataset. An additional CNN tracked key points for antennal pose estimation. Motor analysis showed that the LC₃₀ of carlina oxide reduced average speed and distance, induced altered exploratory behaviour, and affected thigmotaxis. Statistically significant features were evaluated using machine learning classifiers: random forest, support vector machine, and K-nearest neighbours. The analysis comparing control and treated groups distinguishes LC₃₀ and LC₁₀ from the control group, while SHapley Additive exPlanation (SHAP) analysis explained the features contribution to predictions.

Conclusions: Metrics poorly distinguish individuals in the LC₁₀ and LC₃₀ classes, supporting the employment of lower sublethal concentration for the control of P. truncatus. However, our findings indicate possible neuroethological effects of green pesticides on sensory systems, highlighting the need for an accurate risk assessment to minimize ecosystem impacts and supporting integrated pest management within One-Health and Eco-Health frameworks. © 2026 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Background: Black spot disease is a significant disease during the growth period of pear trees. The species and pathogenicity of Alternaria fungi causing black spot disease in Anhui Province are still unclear.

Results: In this study, through phylogenetic analysis of multi-gene tandem sequences, pathogens causing pear black spot disease (PBS) in Anhui Province were identified, primarily Alternaria alternata, Alternaria gaisen and Alternaria tenuissima, with A. alternata being the dominant species (41.18%). The single nucleotide polymorphism (SNP) density of Alt a1 was much higher than that of other genes, and the codon bias was affected by both natural selection and mutation. The codon bias and the amino acid ratio of Alt a1 in A. alternata and A. gaisen were highly consistent, and A. tenuissima was quite different from them. The pathogenicity of A. alternata was significantly negatively correlated with the daily mycelia growth rate, dry weight of mycelia and alternariol production, and significantly positively correlated with tenuazonic acid (TeA) and tentoxin production. TeA might be the main virulence factor in the pathogenic process of A. alternata.

Conclusion: This study presents novel ideas for classifying Alternaria fungi and provides a theoretical basis for establishing prevention and control technologies for PBS control and toxin reduction. © 2026 Society of Chemical Industry.