摘要
为明确球孢白僵菌的各项生物学指标与其对小菜蛾致病力间的相关性,对一株球孢白僵菌菌株GXU-Bb进行单孢分离,测定了菌株GXU-Bb及其分离子菌株GXU-Bb16、GXU-Bb10、GXU-Bb13和GXU-Bb05这5个菌株的生长速率、产孢量、孢子萌发率、胞外蛋白酶水平和几丁质酶水平等多项生物学指标。结果表明,各菌株间生长速率和孢子萌发率无显著差异;产孢量变化范围1.54×10^7-2.98×10^7个/ml;胞外蛋白酶水平变化范围1.04-1.19;几丁质酶水平变化范围1.05-1.14;各菌株间对小菜蛾二龄幼虫的致病力差异较大,校正死亡率变化范围为39.81%-83.79%。将各生物学指标与菌株对小菜蛾二龄幼虫的校正死亡率进行回归分析得出,球孢白僵菌对小菜蛾的致病力与菌株生长速率、孢子萌发率无显著相关关系;与产孢量、胞外蛋白酶水平呈极显著正相关关系;与几丁质酶水平呈显著正相关关系。
To explicit the correlation between biological characteristic and virulence of Beauveria bassiana to Plutella xylostella,five B.bassinana strains,including parental strain GXU-Bb and its four single-spore isolations were assayed on the growth rate,sporulation,spore germination rate,extracellular protease level,chitinase level and their virulence to the second instar larvae of P.xylostella.Results showed there was no significant difference in growth rate and spores germination rate among the strains.The sporulation of these strains was 1.54×10^7-2.98×10^7 conidial/ml.The extracellular protease level and chitinase level were 1.04-1.19 and 1.05-1.15,respectively.The corrected mortality of each strain to the second instar larvae was 39.81%-83.79%.Factors affecting the virulence were analyzed based on the correlation coefficient（r）.The virulence of B.bassiana strains against P.xylostella was not affected by the growth rate and spore germination rate,but was positively correlated with the sporulation,extracellular protease level and chitinase level.
出处
《中国生物防治》
CSCD
北大核心
2010年第2期143-148,共6页
Chinese Journal of Biological Control
基金
公益性行业(农业)科研专项项目(200803001)
广东省农业攻关项目(2006B20301037)
关键词
球孢白僵菌
小菜蛾
生物学特性
致病力
相关性
Beauveria bassiana
Plutella xylostella
biological characteristic
virulence
correlation
