Pesticide Biochemistry and Physiology最新文献

{"title":"Odorant-binding protein MusiOBP10 contributes to the aggregation pheromone sensing in both nymphal and adult Megalurothrips usitatus (Bagnall)","authors":"Gen Xia ,&nbsp;Xiaobin Zheng ,&nbsp;Xiaoli Tian ,&nbsp;Qinli Wang ,&nbsp;Guohui Zhang ,&nbsp;Boliao Li","doi":"10.1016/j.pestbp.2025.106926","DOIUrl":"10.1016/j.pestbp.2025.106926","url":null,"abstract":"<div><div>Odorant-binding proteins (OBPs) play a critical role in insect chemoreception by facilitating the transport of odorant molecules to olfactory receptors, thereby initiating signal transduction. <em>Megalurothrips usitatus</em> is a significant pest posing a major threat to leguminous crops, with both nymphs and adults exhibiting aggregation behavior on cowpea. However, the specific functional role of OBPs in modulating this behavior remains unclear. Here, behavioral assays revealed that both nymphs and adults of <em>M. usitatus</em> showed significant attraction to the aggregation pheromone (2<em>E</em>,6<em>E</em>)-farnesyl acetate. Exposure to this aggregation pheromone significantly upregulated <em>MusiOBP10</em> expression in <em>M. usitatus</em>. <em>MusiOBP10</em> knockdown with RNA interference (RNAi) eliminated <em>M. usitatus'</em> attraction to (2<em>E</em>,6<em>E</em>)-farnesyl acetate. Furthermore, binding assays revealed that MusiOBP10 exhibits exceptionally high binding affinity for (2<em>E</em>,6<em>E</em>)-farnesyl acetate. Molecular docking results indicated that MusiOBP10 binds to (2<em>E</em>,6<em>E</em>)-farnesyl acetate primarily through van der Waals interactions. Molecular dynamic simulations identified six candidate key residues within the MusiOBP10–(2<em>E</em>,6<em>E</em>)-farnesyl acetate complex. Computational alanine scanning and site-directed mutagenesis verified four key amino acid residues critical for the binding of MusiOBP10 to (2<em>E</em>,6<em>E</em>)-farnesyl acetate, with the C-terminal residue Phe122 playing a particularly influential role. In conclusion, <em>MusiOBP10</em> plays a critical role in the perception of the aggregation pheromone in <em>M. usitatus</em>. These findings have improved our molecular understanding of aggregation pheromone recognition by <em>M. usitatus</em>, and have facilitated the development of OBP-based behavioral interference strategies to manage this pest.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"218 ","pages":"Article 106926"},"PeriodicalIF":4.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145885701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ongoing insecticide resistance evolution in beet armyworm via changes in the utilization of pre-existing and new mutations","authors":"Fang Guan ,&nbsp;Bingbing Fang ,&nbsp;Wenjuan Mei ,&nbsp;Suiyu Zeng ,&nbsp;Yihua Yang ,&nbsp;John G. Oakeshott ,&nbsp;Yidong Wu","doi":"10.1016/j.pestbp.2025.106929","DOIUrl":"10.1016/j.pestbp.2025.106929","url":null,"abstract":"<div><div>Little has been known until now about the population genomic processes underpinning pest insect species' rapid and ongoing adaptation to chemical insecticides. This paper elucidates these processes for six mutations encoding resistances to four insecticide classes in Chinese <em>Spodoptera exigua</em>: <em>F116V</em> in <em>CYP9A186</em> against avermectins, <em>T929I</em> and <em>L1014F</em> in <em>VGSC</em> against pyrethroids, <em>V1848I</em> in <em>VGSC</em> against indoxacarb and <em>I4790M</em> and <em>I4790K</em> in <em>RyR</em> against diamides. Whole genome sequencing of 139 individuals from 20 populations across China revealed little genetic differentiation among the populations and soft selective sweeps for all six mutations. Ancestral Recombination Graphs (ARGs) showed at least five of them each had a single origin, with <em>CYP9A186-F116V</em>, <em>VGSC-L1014F</em> and <em>RyR-I4790M</em> and likely also <em>RyR-I4790K</em> arising before use of the corresponding insecticides. <em>VGSC-T929I</em> and <em>VGSC-V1848I</em> arose subsequently in <em>VGSC-L1014F</em> backgrounds. Bioassays of near-isogenic lines showed the double mutant <em>VGSC</em>s enhanced pyrethroid resistance and created pyrethroid/indoxacarb cross-resistance, respectively. While the ARGs predicted the younger <em>RyR-I4790K</em> mutation had overtaken <em>RyR-I4790M</em> in frequency by the time diamides were introduced, the latter has since surged again, to a frequency of ca. 95 %. Thus, <em>S. exigua</em> has evolved resistances to several major insecticides through soft selective sweeps of pre-existing mutations in a panmictic population, supplemented by new mutations that enhance or broaden resistance. The findings demonstrate the power of modern population genomics, including ARG, to reconstruct resistance evolution and, in so doing, improving preparedness for, and pro-active management of, resistance.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"218 ","pages":"Article 106929"},"PeriodicalIF":4.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145885632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of novel tryptamine-based SDHI fungicides inspired by rice phytoalexins: Antifungal activity evaluation and molecular mechanism","authors":"Longzhu Bao ,&nbsp;Hexiang Wang ,&nbsp;Yu Chen ,&nbsp;Jie Deng ,&nbsp;Fang Liu ,&nbsp;Huailong Teng ,&nbsp;Shaoyong Ke","doi":"10.1016/j.pestbp.2026.106965","DOIUrl":"10.1016/j.pestbp.2026.106965","url":null,"abstract":"<div><div>Globally, biotic stress—predominantly caused by plant-pathogenic fungi—results in substantial annual crop losses and significant economic costs, thereby posing a continuing threat to agricultural sustainability. Addressing the dual challenges of limited effective agrochemical availability and rapidly evolving pathogen resistance requires the urgent development of novel green fungicides. Inspired by phytoalexins, we designed a series of new pyrazole-carboxylic acid derivatives incorporating a tryptamine motif as potential succinate dehydrogenase inhibitor (SDHI). Most of the compounds exhibited inhibitory activity against eight common phytopathogenic fungi. Among them, compounds <strong>8</strong> and <strong>23</strong> showed significant activity against <em>Sclerotinia sclerotiorum</em>, with EC₅₀ values of 15.7 μmol/L and 19.8 μmol/L, respectively. Activity tests <em>in vivo</em> revealed that compounds <strong>8</strong> and <strong>23</strong> protected oilseed rape leaves and tomato fruits from infection by <em>Sclerotinia sclerotiorum</em> and <em>Botrytis cinerea</em> at a concentration of 100 μmol/L. The inhibition effects of compounds <strong>8</strong> and <strong>23</strong> against succinate dehydrogenase were 6.13 and 6.16 μmol/L, respectively, better than Thirluzamide (IC₅₀ = 9.38 μmol/L). Scanning electron microscopy analysis, molecular docking, and DFT calculation confirmed that the mode of action of these compounds was similar to Fluopyram. Molecular design inspired by phytoalexins offers a new avenue for further developing succinate dehydrogenase inhibitors.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"218 ","pages":"Article 106965"},"PeriodicalIF":4.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146037767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Amide derivatives as potential SDH inhibitors: Design, synthesis, antifungal activity, and preliminary mechanism","authors":"Mei Zhu ,&nbsp;Feng Tian ,&nbsp;Zengxue Wu ,&nbsp;ShuJing Yu ,&nbsp;Jixiang Chen","doi":"10.1016/j.pestbp.2026.106960","DOIUrl":"10.1016/j.pestbp.2026.106960","url":null,"abstract":"<div><div>Plant pathogenic fungi cause plant diseases that affect global food security, and the use of chemical fungicides remains the primary strategy for controlling fungal diseases. A series of amide derivatives containing 3-chloro-5-trifluoromethyl pyridine and piperidine structures was designed and synthesized, and their antifungal activity was systematically evaluated. Among them, compound <strong>M3</strong> exhibited excellent fungicidal efficacy against <em>Rhizoctonia solani</em> (<em>R. s</em>) (EC₅₀ = 3.24 mg/L), with a curative effect of 69.98% at 200 mg/L in rice plants. Compound <strong>M3</strong> inhibited the mycelial dry weight and sclerotial formation of <em>R. s</em>, as well as disrupted the mycelial morphology and ultrastructure, increasing cell membrane permeability, leakage of cell contents, and accumulation of reactive oxygen species (ROS), ultimately leading to fungal death, thus suppressing its growth and reproduction. Compound <strong>M3</strong> significantly inhibited succinate dehydrogenase (SDH) activity (IC₅₀ = 28.40 μM), and molecular docking results also indicated a stable binding mode between compound <strong>M3</strong> and SDH.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"218 ","pages":"Article 106960"},"PeriodicalIF":4.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146037766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative roles of four TFIIH subunits (Tfb1, Tfb2, Tfb4 and Tfb5) in anti-UV and insecticidal processes of Beauveria bassiana","authors":"Min Li,&nbsp;Jian-Ru Feng,&nbsp;Sheng-Hua Ying,&nbsp;Ming-Guang Feng","doi":"10.1016/j.pestbp.2026.106966","DOIUrl":"10.1016/j.pestbp.2026.106966","url":null,"abstract":"<div><div>The transcription factor TFIIH features a core seven-subunit subcomplex required for nucleotide excision repair (NER) of UV-induced DNA damage in budding yeast, but comprising two Rad3 paralogs (Rad3A/B) and orthologs (Rad25, Ssl1, and Tfb1/2/4/5) of the remaining subunits in <em>Beauveria bassiana</em>, a wide-spectrum mycopesticide prone to solar UV damage. Rad25 and Rad3B were previously shown to have high photoreactivation activities in UVB damage recovery and pleiotropic effects in the fungal lifecycle. Presently, only Tfb5 was proven to have higher activity than Tfb1 in photoreactivation of UVB-impaired conidia and similar roles of Rad25 and Rad3B essential for the fungal lifecycle and insecticidal action. Tfb2 and Tfb4 exhibited no anti-UVB activity but a role in early conidiation. Yeast two-hybrid assays revealed complicated interaction networks among the subunits and many other anti-UV proteins that function in the yeast NER pathway but have higher photoreactivation than dark reactivation activities in <em>B. bassiana</em>. The interaction networks implicate that the subcomplex is formed by seven subunits excluding Rad3A and is tightly linked to not only multiple anti-UV protein complexes with high photoreactivation activities but also two photolyases (Phr1/2) and two photolyase regulators (WC1/2), which enable the formation of a white-collar complex serving as blue-light sensor and key transcription factor in fungal circadian system and the photorepair of DNA damage in <em>B. bassiana</em>. Our findings fill a gap in knowledge about the core subcomplex of a filamentous fungus and unveil a scenario that is mechanistically distinct from the same subcomplex needed for the yeast NER-relying anti-UV activity.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"218 ","pages":"Article 106966"},"PeriodicalIF":4.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146037860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification and validating native biocontrol bacteria Bacillus strain MZ3-12 against bacterial wilt","authors":"Xiao Zhou ,&nbsp;Yue Qing ,&nbsp;Yanping Wang ,&nbsp;Haibin Deng ,&nbsp;Jun Wang ,&nbsp;Mi Kuang ,&nbsp;Xuefeng Luo ,&nbsp;Chenran Zhao ,&nbsp;Zheng Sun ,&nbsp;Ye Wang ,&nbsp;Liang Yang ,&nbsp;Wei Ding","doi":"10.1016/j.pestbp.2026.106943","DOIUrl":"10.1016/j.pestbp.2026.106943","url":null,"abstract":"<div><div>Tobacco bacterial wilt is a major threat to sustainable tobacco agriculture. To identify native biocontrol agents for managing this disease, this study integrated rhizosphere microbiome profiling with functional screening. Comparative 16S rDNA amplicon sequencing showed that disease-affected soils had higher abundances of pathogen-linked genera, while healthy soils were enriched in beneficial microbes such as <em>Bacillus</em> and <em>Streptomyces</em>. Then, we isolated thirty potential bacteria from healthy rhizospheres soil, and investigated the effect of screening potential bacteria on <em>R. solanacearum</em> growth, siderophore secretion, protease activity, and cellulase activity. Among these bacteria, four potential biocontrol bacteria were screened, including three <em>Bacillus</em> MZ3–12, MZ4–13, MZ9–28, and a <em>Glutamicibacter</em> MZ8–15. These strains significantly inhibited <em>R. solanacearum</em> growth and secreted highly active proteases, cellulases, and siderophores. They also promoted tobacco growth, increased plant dry weight and fresh weight, and enhanced the expression levels of genes related to the salicylic acid, jasmonic acid, and ethylene pathways. Furthermore, MZ3–12 displays considerable control effect on tobacco bacterial wilt in greenhouse and field conditions. Our results confirm that combining microbiome analytics with culture-based screening is an effective way to identify environment-friendly biocontrol agents, highlighting the role of <em>Bacillus</em> MZ3–12 in maintaining rhizosphere health and managing tobacco bacterial wilt.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"218 ","pages":"Article 106943"},"PeriodicalIF":4.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145939676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Citral-based acylthiourea derivative enhances the efficacy of thiophanate-methyl against Rhizoctonia solani through membrane destabilization","authors":"Xiaoyi Pan ,&nbsp;Hongyan Si ,&nbsp;Suhua Yuan ,&nbsp;Wuxiong Wang ,&nbsp;Guoxiang Liao ,&nbsp;Wenjing Yuan ,&nbsp;Ji Zhang ,&nbsp;Jie Song ,&nbsp;Shangxing Chen ,&nbsp;Zongde Wang ,&nbsp;Shengliang Liao","doi":"10.1016/j.pestbp.2025.106911","DOIUrl":"10.1016/j.pestbp.2025.106911","url":null,"abstract":"<div><div><em>Rhizoctonia solani</em> is a highly destructive fungal pathogen of rice, and effective management currently depends heavily on chemical fungicides such as thiophanate-methyl (TM). To establish a sustainable approach for enhancing fungicide efficacy, we screened 22 citral-based acylthiourea derivatives and identified compound e3 as a highly effective synergist of thiophanate-methyl (TM), achieving a synergistic ratio of 3.88. When the molar ratio of e3 is 20 %, the mixture of e3 and TM (SETM) exhibits a pronounced antifungal activity against <em>R. solani</em>, both in vivo and in vitro. Integrated transcriptomic and metabolomic analyses demonstrated that steroid biosynthesis and membrane lipid metabolism were the primary pathways affected following the addition of e3. Notably, genes including Cytochromes P450 and sterol reductase ERG24 were significantly upregulated and exhibited strong correlations with multiple membrane lipid metabolites. Physiological and biochemical analyses revealed that e3 could induce an increase in ergosterol content, promote the accumulation of reactive oxygen species (ROS), and enhance the activity of antioxidant enzymes. Furthermore, SETM exhibited additional effects by increasing membrane permeability, causing intracellular substance leakage, and inhibiting energy metabolism. Importantly, the incorporation of e3 did not enhance the cytotoxicity of TM toward mammalian cells. These findings show that e3 is a highly effective synergist that disrupts fungal membrane lipid homeostasis and impairs key physiological functions, significantly enhancing TM's antifungal activity. The study advances understanding of fungicide–synergist interactions and offers a sustainable strategy to improve efficacy without sacrificing safety.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"218 ","pages":"Article 106911"},"PeriodicalIF":4.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145842448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Disrupting cytomembrane function mediates the antifungal activity of carvacrol against Sclerotium rolfsii","authors":"Liting Chen ,&nbsp;Xingchen Zhao ,&nbsp;Tangbo Cao ,&nbsp;Qinqin Wang ,&nbsp;Meizi Wang ,&nbsp;Jingjing Zhang ,&nbsp;Xuewei Mao ,&nbsp;Yun Duan ,&nbsp;Lin Zhou","doi":"10.1016/j.pestbp.2025.106903","DOIUrl":"10.1016/j.pestbp.2025.106903","url":null,"abstract":"<div><div>Peanut stem rot (PSR), caused by the fungus <em>Sclerotium rolfsii</em>, is a devastating plant disease that causes severe yield losses and substantial economic impacts in agriculture worldwide. Carvacrol, a natural compound with broad-spectrum antifungal properties, shows significant inhibitory effects on various pathogens. In this study, carvacrol and nano-carvacrol demonstrated strong antifungal activity against <em>S. rolfsii</em>, with 50 % effective concentration (EC₅₀) values of 39.46 mg/L and 19.20 mg/L, respectively. Carvacrol and nano-carvacrol can reduce mycelial growth and suppress the formation and germination of sclerotia. Scanning and transmission electron microscopy revealed carvacrol-induced mycelial deformation and ultrastructural damage. Carvacrol also increases membrane permeability, leading to cell death. Transcriptome analysis with GO/KEGG enrichment revealed that carvacrol disrupted cell membrane biosynthesis, inhibited ergosterol biosynthesis, and interfered with the endoplasmic reticulum pathway. The results of propidium iodide staining of fungal mycelium treated with carvacrol exhibited pronounced PI fluorescence, indicating a general loss of membrane integrity, complete loss of viability, and irreversible membrane damage. qPCR results revealed downregulation of key genes involved in ergosterol biosynthesis and those of cytochrome P450. Both greenhouse and field trials have confirmed that carvacrol and nano-carvacrol have a high control efficacy against PSR, with protective effects superior to those of curative treatments. These findings highlight carvacrol's potential as an eco-friendly fungicide with a novel mode of action.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"218 ","pages":"Article 106903"},"PeriodicalIF":4.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145808337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The fungal biocontrol agent Beauveria bassiana expresses a HsbA domain-containing protein to postpone the rapid cuticle penetration outwards from the insect cadavers","authors":"Zhuoyue Lu ,&nbsp;Zhi Yang ,&nbsp;Ke Li ,&nbsp;Menglin Wu ,&nbsp;Hang Zhang ,&nbsp;Zhibing Luo ,&nbsp;Juan Deng ,&nbsp;Huifang Wang ,&nbsp;Yongjun Zhang","doi":"10.1016/j.pestbp.2026.106958","DOIUrl":"10.1016/j.pestbp.2026.106958","url":null,"abstract":"<div><div>The insect biocontrol fungi (IBF) ‘hidden’ within the dead insect bodies come out of the insect cadavers for dissemination until the suitable environment conditions arising. However, details of the IBF balancing fungal cells ‘hidden’ within the cadavers and penetration of the cuticle outwards for growth remain limited. Here, a HsbA domain-containing protein, BbHsbA, was found to express during the later stages of insect colonization in an IBF, <em>Beauveria bassiana</em>, which distributed in cytoplasm and cell wall. <em>BbHsbA</em> disruption did not significantly affect fungal virulence, while the mutant penetrated the cuticle from the inside-out for growth on the cadaver surface rapidly as compared to the wild type strain, accompanying with elevated lipid droplet (LD) levels. Conversely, <em>BbHsbA</em> overexpression significantly decreased LD content while increased cell wall chitin and glycoprotein levels, resulting in reduced virulence and delayed cuticle penetration outwards from the cadavers. Furthermore, BbHsbA was found to interact with the LD membrane protein perilipin and the peroxisome protein peroxin 14, balancing lipid synthesis and storage while also contributing to cell wall homeostasis as a cell wall component within the insect cadavers. The distinct traits between the gene disruption and overexpression strains were in line with the altered expression patterns of lipid metabolism, chitin hydrolysis and other cell wall biosynthesis-associated genes. These results demonstrate that <em>B. bassiana</em> expresses BbHsbA during the later stages of insect colonization to postpone the rapid cuticle penetration outwards from the dead insect bodies via orchestrating lipid metabolism and cell wall-synthesis homeostasis within the cadavers.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"218 ","pages":"Article 106958"},"PeriodicalIF":4.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146037765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The F116V mutation and overexpression of CYP9A186 confer high-level resistance to emamectin benzoate and abamectin in Spodoptera exigua","authors":"Qiuxia Zeng ,&nbsp;Lin Li ,&nbsp;Yongsheng Yao ,&nbsp;Bingbing Fang ,&nbsp;Yu Shi ,&nbsp;Yihua Yang ,&nbsp;Yidong Wu","doi":"10.1016/j.pestbp.2026.106969","DOIUrl":"10.1016/j.pestbp.2026.106969","url":null,"abstract":"<div><div>The beet armyworm, <em>Spodoptera exigua</em>, is a polyphagous, migratory pest of worldwide importance. It has developed serious resistance to emamectin benzoate and abamectin due to the widespread use of these insecticides in pest control. Previous research demonstrated that the F116V mutation in CYP9A186 confers 265-fold resistance to emamectin benzoate (EB) and 45-fold resistance to abamectin in the WH-EB strain of <em>S. exigua</em>, a near-isogenic strain obtained by introgression of field resistance into the susceptible WH-S line via repeated backcrossing. Here, we examine the contribution of CYP9A186 in a 2024 field population from Alaer, Xinjiang, China (named ALE24), in which the F116V mutation is fixed. The F116V allele from ALE24 was introgressed into the susceptible WH-S strain through repeated backcrossing, yielding a near-isogenic strain (WH-ALE). WH-ALE exhibited 1286-fold resistance to EB and 300-fold resistance to abamectin, which is approximately 5 times greater than that of WH-EB for each respective insecticide. In addition, WH-ALE showed low levels of cross-resistance (2.8- to 4.7-fold) to indoxacarb, esfenvalerate, spinosad, chlorpyrifos, and chlorantraniliprole, but no cross-resistance to chlorfenapyr or broflanilide. Importantly, WH-ALE showed dramatically elevated expression of the mutant <em>CYP9A186</em> allele, with a 72.9-fold increase in the midgut and a 56.8-fold increase in the fat body relative to the WH-S strain, indicating strong metabolic amplification. These results demonstrate that high-level resistance to EB and abamectin in WH-ALE is conferred by the combined effects of the F116V substitution and its marked overexpression. Therefore, resistance monitoring programs should assess both the presence and expression levels of specific resistance alleles of <em>CYP9A186</em> in <em>S. exigua</em> populations to improve adaptive resistance management.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"218 ","pages":"Article 106969"},"PeriodicalIF":4.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146037865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}