球孢白僵菌继代培养中通过菌落局变产生不同类型分离株。本试验检测结果显示此类分离株多表现为产孢量下降、生长速率增加、毒力降低等与生产性状退化类似的变异现象。少数产孢量高、毒力强的分离株，固其生长速率慢即在培养中被掩盖而消失，并据此推断出继代培养次数对该菌退化速率的影响。提出了控制该菌菌种退化的有效措施。 Beauveria bassiana subcultures produce different types of isolates through colony-forming. The test results show that these isolates more performance spores yield decreased, increased growth rate, reduced virulence and other traits of degradation similar to the phenomenon of degradation. A few sporulation and virulent isolates, whose growth rate was slow, were masked and disappeared in culture, and deduced the effect of subculture number on the degradation rate of the strain. Proposed effective measures to control the degeneration of the bacteria.