以高毒力苏云金芽孢杆菌(Bacillus thuringiensis,Bt)为供试菌株,以二化螟为试虫,初步研究了30个Bt菌株对1~2龄二化螟幼虫的毒力效果,进而以筛选出的5株较高青力Bt菌株进行2~3龄二化螟幼虫青力试验,以筛选出适合黑龙江省二化螟防治的Bt菌株。结果表明:Bt14菌株在饲喂菌液168h后,二化螟的校正死亡率可达90%以上,毒力回归方程为y=0.6121x+0.8789,R2=0.9989,LC50=5.4×106芽孢/mL,致死剂量与其它菌株差异显著,表明该菌株对防治二化螟具有很好的应用前景。 The high virulence of Bacillus thuringiensis (Bacillus thuringiensis, Bt) as tested strains, the Chilo suppressalis as test insects, preliminary study of 30 strains of Bt 1 to 2 age insects Chilo suppressalis larvae virulence, and then screening The 5 strains of higher green Bt strains were used to test larvae larvae of 2 ~ 3 instar larvae to screen out Bt strains suitable for the control of Chilo suppressalis in Heilongjiang Province. The results showed that the corrected mortality of Bt14 was over 90% after 168 h feeding, the regression equation was y = 0.6121x + 0.8789, R2 = 0.9989, LC50 = 5.4 × 106 spores / mL , The lethal dose was significantly different from other strains, indicating that the strain has a good application prospect for the control of the stem borer.