论文部分内容阅读
生长前期转 Bt基因棉对低龄棉铃虫幼虫具较强的抗性 ,子叶期抗性最强 ,真叶后下降 ,随后逐渐上升 ,至 1 0叶期达顶点 ,之后又开始下降 ;沿江棉区一代棉铃虫幼虫发生期 ,正处于 Bt基因棉的生长前期 ,转 Bt基因棉对 1龄和 2龄幼虫在较短的时间内即表现出较强的抗虫效果 ,对 3龄和4龄幼虫抗虫效果明显下降 ,但连续取食后全部不能存活 ,对 5龄幼虫抗虫效果较差 ,连续取食后可部分化蛹但化蛹率明显低于对照。同时测定了降雨对生长前期转 Bt基因棉抗性表达的影响
The transgenic Bt cotton had stronger resistance to the young cotton bollworm larvae at the early growth stage, the strongest resistance at the cotyledon stage, the true leaf fall, and then gradually increased until reaching the apex at 10 and then began to decline again. The first generation cotton bollworm larvae were in the early growth stage of Bt cotton. The transgenic Bt cotton showed strong resistance to the first and second instar larvae in a relatively short period of time. The 3rd and 4th instar larvae The insect resistance decreased obviously, but all of them could not survive after continuous feeding. The insecticidal effect on the 5th instar larvae was poor. After continuous feeding, the pupae could be partially differentiated but the pupation rate was significantly lower than that of the control. At the same time, the effect of rainfall on resistance expression of transgenic Bt cotton during early growth period was also measured