茴香薄翅野螟病原真菌鉴定及其致病力评估  

Identification and Pathogenicity Evaluation of Pathogenic Fungi from Evergestis extimalis

作　　者：马有花 来有鹏 MA Youhua;LAI Youpeng(Key Laboratory of Plateau Ecology and Agriculture/Key Laboratory of Agricultural Integrated Pest Management of Qinghai Province,Qinghai University,Xining 810016,China)

机构地区：[1]青海大学三江源生态与高原农牧业国家重点实验室/青海省农业有害生物综合治理重点实验室,青海西宁810016

出　　处：《江西农业大学学报》2022年第5期1112-1121,共10页Acta Agriculturae Universitatis Jiangxiensis

基　　金：青海省重大科技专项(2019NKA11)

摘　　要：【目的】明确茴香薄翅野螟(Evergestis extimalis Scopoli,1763)幼虫患病个体上的病原菌种类,为该虫的生物防治提供理论依据。【方法】对感菌的茴香薄翅野螟幼虫经室内分离培养,以菌丝生长速度与产孢量为指标筛选出菌株生长的最适培养基,结合形态学及 rDNA-ITS 序列相似性分析鉴定病原真菌并采用浸渍法测定其对该虫的致病性。【结果】病原真菌为冻土毛霉(Mucor hiemalis,1903),适宜生长的最优培养基是萨氏葡萄糖琼脂酵母膏(SDAY)培养基,该菌对茴香薄翅野螟幼虫均有一定致病力,处理 9 d 后 2、3、4 和 5 龄幼虫累计死亡率分别为 71.78%,49.44%,46.51% 和 28.89%,且侵染率随时间的推延而增大;该菌株在侵染茴香薄翅野螟 2 龄幼虫 8 d 后,LC_(50)为 1.02×10^(5)孢子/mL,LT_(50)为 3.73 d。【结论】冻土毛霉(M.hiemalis)在茴香薄翅野螟的防治方面有生防潜力。[Objective]This study aims to identify the species of pathogen on the carcasses of Evergestis extimalis Scopoli 1763 larvae,thus providing theoretical basis for biological control of E.extimalis.[Method]Inthis study,the infected larvae of E.extimalis were isolated and cultured in laboratory,and the optimum mediumfor the growth of the strain was selected according to the mycelial growth rate and spore yield.The pathogenicfungus was identified by morphological characterization and rDNA-ITS sequence analysis,and its pathogenicityto the larvae of E.extimalis was determined by impregnation method.[Result]The isolated fungus was identi-fied as Mucor hiemals,and the optimal medium for growth was SDAY medium.The strain could infect the 2nd-5th instar larvae of E.extimalis,the cumulative mortality was 71.78%,49.44%,46.51% and 28.89% respectively af-ter 9 days of treatment,and the infection rate increased with time.After infecting the 2ndinstar larvae of E.extimalis for 8 days,LC50was 1.02×10^(5)spores/mL,LT50was 3.73 d,respectively.[Conclusion]M.hiemalishas bio-control potential of E.extimalis.

关 键 词：茴香薄翅野螟 病原真菌 冻土毛霉 致病力 

分 类 号：S435.73[农业科学—农业昆虫与害虫防治] S476.12[农业科学—植物保护]