【摘要】 小菜蛾是河北坝上错季蔬菜生产区最重要的害虫,为了探索对其无公害治理方法,以张北的小菜蛾为试虫,测定了33株球孢白僵菌对其幼虫的僵虫率,从中筛选出5株对小菜蛾2龄幼虫有较高致病力的菌株;从致死中浓度(LC50)和致死中时(LT50)的测定结果分析,BD-B026菌株的毒力最高,其处理后7d的LC50为0.47×105个/mL孢子,含1.0×108个/mL孢子菌液的LT50为(1.57±0.027)d,对小菜蛾表现出较强的致病力,具有一定的开发前景。更多还原

【Abstract】 The diamondback moth,Plutella xylostella,is a serious pest in vegetable fields in Zhangbei.Bio-efficacy of Beauveria bassiana,an entomopathogenic fungus,was evaluated against the 2nd larvae of this pest in the laboratory.The virulence and efficacy rate of 33 isolates were compared with each other,and 5 isolates were obtained.The results showed that BD-026 is the best among these isolates.The LC50(7 days)was 0.47×105 spores/mL and the LT50(1.0×108 spores/mL)was(1.57±0.027)days.This results indicated that BD-026 might be a good bio-pesticide in practice in the future.更多还原