苏云金杆菌对中华稻蝗的毒力和致染色体畸变研究

TOXICITY AND GENETOXICITY OF BACILLUS THURINGINENSIS (BERLINER) TO OXYA CHINENSIS(THUNBERG)

本研究采用注射法测定了苏云金杆菌 (Bacillusthuringiensis,B .t)对中华稻蝗 5龄蝻和初羽化成虫的毒力。结果显示 ,B .t对中华稻蝗蝻和成虫均有一定的杀伤力。在 4 8h ,B .t对蝻和成虫的毒力回归线分别为 y =1 15 + 2 61x (相关系数r =0 993 8)和 y =2 0 6+ 2 11x (r =0 992 1) ,LD50 分别为 0 18IU/头和 0 2 0IU/头 ,蝗蝻较成虫对药剂稍敏感 ;成虫在 2 4h的LD50 ( 0 2 7IU/头 )比 4 8h的LD50 ( 0 2 0IU/头 )大 ,在较短的作用时间达到同样的杀伤效果需要较高的作用效价。此外 ,还观察分析了B .t悬浮液对 5龄蝗蝻精巢细胞染色体的致畸效应。结果发现 ,B .t可诱发蝗蝻一定比例的染色体畸变 ,其畸变类型主要是染色单体断裂和染色体断裂。统计分析认为 ,它是一种较强的致蝗虫染色体畸变剂。

In this paper, B.t's toxicity to the 5th larves and fledgling adults of Oxya chinensis (Thunberg) was assayed by injecting. The results showed that for the effect of B.t to nymphs and adults, at 48 h time point, the linear regression relationship between the logarithm(x) of B.t's dose and the probability(y) of corrected mortality were y=1.15+2.61x (correlative coefficient r=0.9938), LD 50=0.18 IU/insect and y=2.06+2.11x(r=0.9921),LD 50=0.20 IU/insect, respectively. The 5 th larves were more susce...