北方农业学报2025，Vol.53Issue(5)：57-66,10.DOI:10.12190/j.issn.2096-1197.2025.05.06
嗜线虫沙雷氏菌对小菜蛾高毒力菌株的筛选及毒力测定
Screening and virulence determination of highly virulent strains of Serratia nematodiphila against Plutella xylostella
摘要
Abstract
[Objective]To screen highly effective microbial biocontrol strains against Plutella xylostella.[Methods]The strains of Serratia nematodiphila(FQ268,LJ232,YC310,and YC278)were subjected to physiological and biochemical characterization.High-activity strains were screened using the leaf-dip method,followed by antibiotic susceptibility testing and insecticidal virulence determination against P.xylostella.[Results]All four S.nematodiphila strains were Gram-negative.The methyl red test,indole test,cellulose degradation test,and lipase activity test were negative,while the catalase test and citrate utilization test were positive.All four strains could utilize glucose and mannitol to produce acid but could not utilize fructose and inositol.The high-activity strain identified was S.nematodiphila FQ268,which was susceptible to ceftriaxone,gentamicin sulfate,and norfloxacin,but resistant to rifampicin,cefradine,penicillin,erythromycin,and tetracycline.The fermentation broth of S.nematodiphila FQ268(5.58×109 CFU/mL)exhibited LC50 values of 1.742×109 and 2.566×107 CFU/mL against second-instar larvae of P.xylostella at 48 and 72 h,respectively.[Conclusion]S.nematodiphila FQ268 shows high insecticidal activity against second-instar larvae of P.xylostella and represents a relatively efficient microbial biocontrol strain.关键词
嗜线虫沙雷氏菌/小菜蛾/菌株筛选/毒力测定Key words
Serratia nematodiphila/Plutella xylostella/Strain screening/Virulence determination分类
农业科技引用本文复制引用
许超莹,杨超凡,宋萍,李鑫,南宫自艳..嗜线虫沙雷氏菌对小菜蛾高毒力菌株的筛选及毒力测定[J].北方农业学报,2025,53(5):57-66,10.基金项目
湖南省重点研发计划项目(2023NK2030) （2023NK2030）
湖南省农业科技创新资金项目(2024CX115) （2024CX115）
