Pesticide Biochemistry and Physiology最新文献

{"title":"Co-application of Validamycin A and dsRNAs targeting trehalase genes conferred enhanced insecticidal activity against Laodelphax striatellus","authors":"Hainan Zhang ,&nbsp;Hai Li ,&nbsp;Shu Fang ,&nbsp;Daojie Guan ,&nbsp;Jiaping Wei ,&nbsp;Zhichao Wang ,&nbsp;Zhichao Luo ,&nbsp;Kun Qian ,&nbsp;Jianjun Wang","doi":"10.1016/j.pestbp.2024.106160","DOIUrl":"10.1016/j.pestbp.2024.106160","url":null,"abstract":"<div><div>The small brown planthopper (SBPH), <em>Laodelphax striatellus,</em> poses a significant threat to rice crops, necessitating innovative pest control strategies. This study evaluated the potential of validamycin A (Val A) and RNA interference (RNAi) targeting <em>trehalase</em> genes (<em>LsTre1</em> and <em>LsTre2</em>) in controlling SBPH. Our results demonstrated that Val A treatment of rice seedlings led to a dose-dependent mortality of SBPH. Concurrently, Val A induced the upregulation of <em>LsTre1</em> and <em>LsTre2</em>, suggesting a compensatory feedback mechanism. Furthermore, foliar-applied chimeric dsRNA targeting <em>LsTre1</em> and <em>LsTre2</em> exhibited higher insecticidal activity than individual dsLsTre1 and dsLsTre2 or mixed dsRNAs. Remarkably, co-application of Val A and chimeric dsRNA increased SBPH mortality due to the suppression of Val A-induced <em>LsTre1 and LsTre2</em> upregulation by chimeric dsRNA. These results suggest that the co-application of Val A and chimeric dsRNA targeting <em>trehalase</em> genes could be an effective SBPH control strategy.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"205 ","pages":"Article 106160"},"PeriodicalIF":4.2,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416938","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":"Baseline sensitivity and resistance risk of Sclerotinia sclerotiorum to glabridin and the possible anti-fungal mechanism","authors":"Shu Xu ,&nbsp;Chenyang Liu ,&nbsp;Jin Chen ,&nbsp;Linwei Li ,&nbsp;Siwei Qiao ,&nbsp;Mei Tian ,&nbsp;Qian Zhou ,&nbsp;Xingzeng Zhao ,&nbsp;Yu Chen ,&nbsp;Fei Liu ,&nbsp;Xu Feng","doi":"10.1016/j.pestbp.2024.106162","DOIUrl":"10.1016/j.pestbp.2024.106162","url":null,"abstract":"<div><div>Sclerotinia stem rot caused by <em>Sclerotinia sclerotiorum</em> is one of the most serious diseases of oilseed rape. Chemical control is an important method to control this disease, however, development of fungal resistance to commonly used fungicides has led to severe yield losses in recent years. Therefore, development of novel fungicides against <em>S. sclerotiorum</em> is urgently needed. Glabridin is one of the major flavonoids in <em>Glycyrrhiza</em> L. plants, and we previously found that it is very effective against <em>S. sclerotiorum</em>. Nevertheless, the baseline sensitivity and resistance risk of <em>S. sclerotiorum</em> to glabridin as well as the possible anti-fungal mechanism need further elucidation. In this study, we revealed that the EC₅₀ (median effective concentration) values of glabridin against 109 <em>S. sclerotiorum</em> isolates collected from Jiangsu Province of China ranged from 0.51 to 8.03 μg/mL with a mean EC₅₀ value of 3.05 ± 1.27 μg/mL. No cross-resistance was observed between glabridin and carbendazim, and no glabridin-resistant mutants were obtained by chemical induction. RNA profiling result showed that tyrosine metabolism of <em>S. sclerotiorum</em> were evidently affected by glabridin. qRT-PCR, enzyme activity assay, and molecular docking proved that glabridin greatly reduced both the expression level and enzyme activity of tyrosinase in <em>S. sclerotiorum</em>. Furthermore, <em>S. sclerotiorum</em> incurred certain impairment in its membrane integrity after glabridin treatment at 10 μg/mL. This study is the first report on baseline sensitivity and resistance risk of <em>S. sclerotiorum</em> to glabridin, and it is revealed that glabridin may interfere tyrosine metabolism and membrane integrity of <em>S. sclerotiorum</em>.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"205 ","pages":"Article 106162"},"PeriodicalIF":4.2,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416922","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":"Scaffold hopping approach to the novel hexacyclic pyrazol-3-amide derivatives as potential multi-target insect growth regulators candidates","authors":"Bingbo Guo ,&nbsp;Shihui Luo ,&nbsp;Lei Chen ,&nbsp;Chunying Wang ,&nbsp;Yanjiao Feng ,&nbsp;Congwang Cao ,&nbsp;Li Zhang ,&nbsp;Qing Yang ,&nbsp;Xinling Yang","doi":"10.1016/j.pestbp.2024.106163","DOIUrl":"10.1016/j.pestbp.2024.106163","url":null,"abstract":"<div><div>Ecdysone receptor (EcR) and three insect chitinases (<em>Of</em>ChtI, <em>Of</em>ChtII, and <em>Of</em>Chi-h) are considered as attractive targets for the development of novel insect growth regulators (IGRs) since they are closely related to the insect molting. In this study, to develop potent multi-target IGRs, a series of hexacyclic pyrazol-3-amide derivatives were rationally designed by utilizing the scaffold hopping strategy with the previously reported compound <strong>6j (</strong><em>N</em>-(4-bromobenzyl)-2-phenyl-4,5,6,7-tetrahydro-2<em>H</em>-indazole-5-carboxamide) as a lead compound. The bioassay results indicated that most of the target compounds exhibited obvious insecticidal activity. Especially, compounds <strong>a5</strong> and <strong>a21</strong> displayed excellent insecticidal activities against <em>P. xylostella</em> with LC₅₀ values of 82.29 and 69.45 mg/L, respectively, exceeding that of <strong>6j</strong> (263.78 mg/L). Compounds <strong>a5</strong> and <strong>a21</strong> also dramatically disturbed the growth and development of <em>O. furnacalis</em> larvae, and their LC₅₀ values were 124.71 and 127.54 mg/L, respectively, superior to the lead <strong>6j</strong> (267.33 mg/L). The action mechanism study revealed that the most active compound <strong>a21</strong> could act simultaneously on EcR (21.4 % binding activity at 8 mg/L), <em>Of</em>ChtI (94.9 % inhibitory at 10 μM), <em>Of</em>ChtII (23.1 % inhibitory at 10 μM), and <em>Of</em>Chi-h (94.3 % inhibitory at 10 μM), significantly higher than that of the lead compound <strong>6j</strong>. The result of molecular docking indicated that transferring the carboxamide group from pyrazole position 5 to 3 enhanced the interactions of <strong>a21</strong> with the key amino acid residues of the <em>Of</em>ChtI, <em>Of</em>ChtII, and <em>Of</em>Chi-h, resulting in stronger affinity to the three targets than <strong>6j</strong>. The present work offers a useful guidance for the further development of novel multi-target IGRs.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"205 ","pages":"Article 106163"},"PeriodicalIF":4.2,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416759","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":"Functional analyses of dopamine receptors involved in virus transmission and reproduction in the small brown planthopper Laodelphax striatellus","authors":"Gang Xu,&nbsp;Qiuxin Zhang,&nbsp;Mingshi Qian,&nbsp;Liang Wu,&nbsp;Liran Fu,&nbsp;Chenjia Shao,&nbsp;Meiqi Xu,&nbsp;Yuanyuan Zhang,&nbsp;Guoqing Yang","doi":"10.1016/j.pestbp.2024.106157","DOIUrl":"10.1016/j.pestbp.2024.106157","url":null,"abstract":"<div><div>Dopamine (DA) is the most abundant biogenic amine present in the insect central nervous system, and regulates multiple functions in physiology and behaviors through dopamine receptors (DARs). The small brown planthopper <em>Laodelphax striatellus</em> is an important agricultural pest and causes serious damage by transmitting diverse plant viruses, such as rice stripe virus (RSV). However, DARs have not yet been molecularly characterized in planthoppers, and their roles in virus infection and transmission remain largely unknown in insect vectors. In this study, we cloned four <em>LsDARs</em> (<em>LsDOP1</em>, <em>LsDOP2</em>, <em>LsDOP3</em> and <em>LsDopEcR</em>) from <em>L.</em> <em>striatellus</em>. LsDARs share considerable sequence identity with their orthologous DARs, and cluster nicely with their corresponding receptor groups. The transcript levels of <em>LsDARs</em> varied in different developmental stages and adult tissues, with the highest expressions in the egg stage and in the brain. The expression levels of <em>LsDARs</em> were significantly higher in RSV-viruliferous <em>L.</em> <em>striatellus.</em> Knockdown of <em>LsDOP2</em> and <em>LsDOP3</em> significantly downregulated the expressions of viral genes of capsid protein (<em>CP</em>) and RNA3 segment (<em>RNA3</em>), while <em>LsDOP1</em> knockdown upregulated their expressions. Silencing <em>LsDopEcR</em> upregulated and then downregulated <em>CP</em> and <em>RNA3</em> expressions. Moreover, <em>LsDOP2</em> and <em>LsDOP3</em> knockdown significantly decreased the vertical transmission rates of RSV. Meanwhile, DA injection promoted RSV transmission and accumulation. We further demonstrated that silencing of <em>LsDARs</em> significantly altered the expressions of vitellogenin (<em>LsVg</em>) and Vg receptor (<em>LsVgR</em>). Furthermore, the reproduction performance of <em>L.</em> <em>striatellus</em> was reduced by <em>LsDOP2</em> and <em>LsDOP3</em> knockdown, but increased by <em>LsDopEcR</em> knockdown, and not affected by <em>LsDOP1</em> silencing. These results provide critical information concerning the roles of DARs in virus transmission and reproduction in <em>L.</em> <em>striatellus</em>, and open the way for the development of innovative strategies for planthopper control.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"205 ","pages":"Article 106157"},"PeriodicalIF":4.2,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416929","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":"Biological damage of monocrotaline on the brain and intestinal tissues of Apis mellifera","authors":"Qi Hua,&nbsp;Xuepeng Chi,&nbsp;Ying Wang,&nbsp;Baohua Xu","doi":"10.1016/j.pestbp.2024.106158","DOIUrl":"10.1016/j.pestbp.2024.106158","url":null,"abstract":"<div><div>Monocrotaline (MCT) is a toxic alkaloid present in plants, posing a threat to animals in terrestrial ecosystems. However, little is known about its potential impacts on pollinating insects. Here, we report the effects of of MCT on the brains and intestines of foraging honeybees (<em>Apis mellifera</em>). MCT exposure resulted in a reduction in head weight and swelling of the abdomen in honeybees. Additionally, MCT exposure caused morphological damage to the brain, characterized by decreased antioxidant capacity and increased apoptosis, along with intestinal tissue damage that was accompanied by increased antioxidant capacity and apoptosis. Moreover, MCT altered the core gut microbial community structure in honeybees and increased the expression of antimicrobial peptide (AMP) genes in the midgut. These findings indicate that exposure to MCT activates the immune response in the honeybee gut, while the brain does not exhibit an immune response but instead experiences oxidative stress. This study provides a resource for future research exploring interactions between MCT and other insects, and can help deepen our understanding of MCT's potential impacts in ecosystems.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"205 ","pages":"Article 106158"},"PeriodicalIF":4.2,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416937","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":"Enantioselective effects of chiral profenofos on the conformation for human serum albumin","authors":"Wenze Li ,&nbsp;Long Sun ,&nbsp;Xiaofan Yang ,&nbsp;Changsheng Peng ,&nbsp;Rimao Hua ,&nbsp;Meiqing Zhu","doi":"10.1016/j.pestbp.2024.106159","DOIUrl":"10.1016/j.pestbp.2024.106159","url":null,"abstract":"<div><div>Profenofos, as a typical chiral organophosphorus pesticide, can cause various environmental problems and even endanger human health when used in excess. The toxicity of chiral profenofos was investigated through multispectral analysis, molecular docking, and density functional theory (DFT), employing human serum albumin (HSA) as the model protein. Fluorescence titration and lifetime measurements demonstrated that the interaction between chiral profenofos and HSA involves static quenching. Chiral profenofos forms a 1:1 complex with HSA at site II (subdomain IIIA), primarily driven by hydrophobic interactions and hydrogen bonds. Notably, the binding efficacy diminishes as temperature increases. Spectroscopic analyses confirm that chiral profenofos alters the microenvironment and structure of HSA, with the <em>R</em>-enantiomer exerting a greater impact than the <em>S</em>-enantiomer. Consequently, the toxicological implications of the <em>R</em>-profenofos is significantly more pronounced. Investigating the molecular-level toxic effects of chiral pesticides enhances the thoroughness of pesticide assessments, aids in understanding their distribution, metabolism, and associated risks, and facilitates the development of mitigation strategies.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"205 ","pages":"Article 106159"},"PeriodicalIF":4.2,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416919","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":"Transcriptional responses of detoxification genes to coumaphos in a nontarget species, Galleria mellonella (greater wax moth) (Lepidoptera: Pyralidae), in the beehive environment","authors":"Shengyun Li,&nbsp;Wen-Yen Wu,&nbsp;Ling-Hsiu Liao,&nbsp;May R. Berenbaum","doi":"10.1016/j.pestbp.2024.106156","DOIUrl":"10.1016/j.pestbp.2024.106156","url":null,"abstract":"<div><div>The greater wax moth <em>Galleria mellonella</em> is a cosmopolitan pest of hives of the western honey bee <em>Apis mellifera</em>, where it remains exposed to varroicides applied by beekeepers in past decades as pest management chemicals for control of <em>Varroa destructor</em>, a devastating ectoparasite of bees. The prolonged presence of coumaphos residues, an organophosphate varroicide, in beeswax may be responsible for current levels of tolerance exhibited by <em>G. mellonella</em>, a non-target species that infests beehives<em>.</em> In this study, a field-collected strain of waxworms exhibited a higher LC₅₀ value for coumaphos than that of a laboratory strain that had not been continuously exposed to coumaphos residues at field concentrations. Despite its higher tolerance for coumaphos, the field strain experienced growth inhibition at ecologically relevant concentration of coumaphos. Moreover, at low environmental concentrations that did not alter growth, detoxification gene expression levels were substantially altered. RNA-Seq analysis revealed 1181 and 658 differentially expressed genes in fat body and midgut, respectively, with 378 and 186 of those genes upregulated. This large-scale upregulation encompassed 21 genes encoding cytochrome P450 monooxygenases (CYPs), 13 encoding UDP-glycosyltransferases (UGTs), 5 encoding glutathione-S-transferases (GSTs), 2 encoding carboxylesterases (COEs), and 2 encoding ABC transporters (ABCs) in either tissue. Expression analysis of 13 selected candidate detoxification genes by RT-qPCR was consistent with their expression from RNA-Seq data. In sum, our results indicate that long-lasting pesticide residues in beeswax from past Varroa mite management may continue to act as selective agents on detoxification systems of hive residents other than the initial target species and that multiple resistance mechanisms to these chemicals may coexist within the beehive fauna.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"205 ","pages":"Article 106156"},"PeriodicalIF":4.2,"publicationDate":"2024-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416921","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":"Citrus exosome-modified exogenous dsRNA delivery reduces plant pathogen resistance and mycotoxin production","authors":"Chunxiao Yin ,&nbsp;Yuli Lao ,&nbsp;Lihong Xie ,&nbsp;Lianfei Chen ,&nbsp;Yueming Jiang ,&nbsp;Liang Gong","doi":"10.1016/j.pestbp.2024.106151","DOIUrl":"10.1016/j.pestbp.2024.106151","url":null,"abstract":"<div><div>Plant-derived exosome-like nanoparticles (PENs) are crucial for intercellular communication. However, PEN-based transport of pathogenic fungal genes remains unclear. This study isolated and purified PENs from lane late navel orange citrus juice by following the sucrose gradient ultracentrifugation technique. Citrus PENs were round and oval-shaped with an average size of 154.5 ± 1.9 nm. Electroporation-based exogenous dsRNA to PENs loading efficiency remained at 6.0 %. Laser confocal microscopy was employed to investigate citrus PEN uptake by fungal spores. dsCrcB loaded PENs inhibited the CrcB gene expression in spores to alleviate <em>Penicillium italicum</em> resistance against prochloraz fungicide, which promoted resistant strains' mortality by 10-fold. Moreover, dsFUM21-loaded PENs suppressed the FUM21 gene expression in spores, which significantly reduced FB1 production in <em>Fusarium proliferatum</em>. These findings suggest that citrus PENs could potentially serve as nano-carriers to counter fungicide resistance and mycotoxin production in pathogenic plant fungi.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"205 ","pages":"Article 106151"},"PeriodicalIF":4.2,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416920","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":"Resistance risk and resistance-associated point mutations in the target protein PcVHA-a of fluopimomide in Phytophthora capsici","authors":"Jikun Yang ,&nbsp;Tan Dai ,&nbsp;Chuang Zhao ,&nbsp;Zitong Wang ,&nbsp;Jianqiang Miao ,&nbsp;Xili Liu","doi":"10.1016/j.pestbp.2024.106150","DOIUrl":"10.1016/j.pestbp.2024.106150","url":null,"abstract":"<div><div>Fluopimomide, developed by Shandong Sino-Agri United Biotechnology Co., Ltd., is a pyridinylmethyl-benzamide fungicide with good activity against plant diseases caused by phytopathogenic oomycetes. However, there is uncertainty surrounding the resistance risk of fluopimomide and its resistance mechanism in <em>Phytophthora capsici</em>. In this study, the baseline sensitivity of <em>P</em>. <em>capsici</em> to fluopimomide was established, and 106 <em>P</em>. <em>capsici</em> isolates shown sensitive to fluopimomide, with a mean EC₅₀ value of 5.1892 ± 2.2613 μg/mL. Fungicide adaptation produced three fluopimomide-resistant <em>P</em>. <em>capsici</em> mutants, two of which exhibited considerably lower compound fitness index (CFI) than the parent strain, and one showed significantly improved CFI. While cross-resistance was observed between fluopimomide and fluopicolide, no cross-resistance was detected between fluopimomide and other fungicides. Overall, <em>P. capsici</em> presents a moderate resistance risk to fluopimomide. Two point mutations, G767E and K847R, were identified in the V-ATPase subunit a of <em>P</em>. <em>capsici</em> (PcVHA-a) in resistant mutants. These mutations were subsequently validated through site-directed mutagenesis and molecular docking assays, confirming their roles in conferring fluopimomide resistance in <em>P</em>. <em>capsici</em>.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"205 ","pages":"Article 106150"},"PeriodicalIF":4.2,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416918","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":"EpOME mediates the immune resolution and its alkoxide analog enhances the virulence of microbial insecticides against the legume pod borer, Maruca vitrata","authors":"Mojtaba Esmaeily ,&nbsp;Wook Hyun Cha ,&nbsp;Dae-Weon Lee ,&nbsp;Minji Kwon ,&nbsp;Dong-Hee Lee ,&nbsp;Anders Vik ,&nbsp;Yonggyun Kim","doi":"10.1016/j.pestbp.2024.106155","DOIUrl":"10.1016/j.pestbp.2024.106155","url":null,"abstract":"<div><div>Excessive and unnecessary immune responses cause serious adverse effects due to self-tissue damage and energy consumption, particularly at the late stage of infection to terminate the induced immunity. Unlike mammals, which use long-chain fatty acid oxylipins, C18 oxygenated polyunsaturated fatty acids are suggested to act as immune resolvins in insects, including two epoxyoctadecamonoenoic acids (9,10-EpOME and 12,13-EpOME). This study investigated the physiological roles of EpOMEs in immune resolution in the lepidopteran insect, <em>Maruca vitrata</em>. The levels of two EpOMEs in the larvae increased during the late infection stage upon immune challenge. At their peak concentrations at 96 h post-infection (pi), both EpOMEs were found at similar levels: 323.18 pg/mg body weight for 9,10-EpOME and 322.07 pg/mg body weight for 12,13-EpOME. Both EpOMEs inhibited cellular and humoral immune responses, with 12,13-EpOME being more potent than 9,10-EpOME. Genes associated with EpOME synthase and degradation, identified as <em>Mv-CYP1</em> and <em>Mv-sEH</em>, were detected in various developmental stages and tissues of <em>M. vitrata</em>. RNA interference (RNAi) targeting <em>Mv-CYP1</em> failed to inhibit the immune response, whereas RNAi targeting <em>Mv-sEH</em> enhanced the immunosuppression. In contrast to the acute (&lt; 12 h pi) immune response involving eicosanoid biosynthesis, the expression of these two genes linked to EpOME metabolism increased significantly at the late infection stage (&gt; 12 h pi). Several alkoxide analogs of EpOME, with the epoxide group replaced by an alkoxide group, were synthesized; one such derivative demonstrated substantially greater efficacy than the natural EpOMEs in inhibiting the immune response. Additionally, using EpOME alkoxide significantly increased the effectiveness of microbial insecticides. Moreover, exposing young larvae to sublethal doses of EpOME alkoxide or sEH inhibitor induced severe developmental delays. These results suggest a novel strategy for insect pest control using insect immune resolvin analogs.</div></div>","PeriodicalId":19828,"journal":{"name":"Pesticide Biochemistry and Physiology","volume":"205 ","pages":"Article 106155"},"PeriodicalIF":4.2,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416767","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}