一株具有杀虫活性真菌的筛选及活性物质稳定性研究

Screening of a Fungus with Insecticidal Activity and Measure of the Stability of Its Bioactive Compound

以卤虫为初筛指示虫,以蚜虫为复筛指示虫,从广西玉林土壤分离筛选出具有杀虫活性的菌株YLZ42。根据培养特征、形态特征及18S rDNA、ITS序列分析,菌株YLZ42被鉴定为淡色生赤壳菌(Bionectria ochroleuca)。生物测定结果表明,YLZ42发酵液的乙酸乙酯萃取物对小菜蛾、棉铃虫、甜菜夜蛾具有明显的毒杀活性,其校正死亡率在78.9%以上。YLZ42发酵液稳定性研究表明,其活性成分在100℃处理60 min,pH1-11条件下仍具有较强的杀虫活性。

Using Brine Shrimp as primary screening assay and Aphid as second screening assay, the YLZ42 strain with insecticidal activity were isolated and screened from the soil in Yulin, Guangxi Province. According to the culture features, morphological characteristics, 18 S rDNA and ITS sequence analysis, YLZ42 was identified as Bionectria ochroleuca. The ethyl acetate extract of YLZ42 fermentation broth have insecticidal activity to Plutella xylostella, Helicoverpa armigera and Laphygma exiguat. Results of bioassay showed that the corrected mortalities rate were more than 78.9%. The fermentation broth have high insecticidal activity under 100℃ for 60 min or pH1-11.