新疆棉区Bt棉对棉铃虫生物学习性的影响

通过室内饲养与田间观察 ,系统研究了Bt棉对棉铃虫生物学习性的影响 ,结果表明 :棉铃虫大龄幼虫取食Bt棉后 ,化蛹率下降 33.3%～ 5 1.7%,羽化率降低 2 6 .3%～ 5 7.8%,蛹重减少 6 .5 %～ 11.4%,对蛹期的影响较小。 5龄幼虫取食Bt棉后单蛾产卵量下降 43.4%～ 6 7.8%,卵孵化率下降 77.1%～ 84.5 %。对用常规棉饲养出的刚羽化的蛾子用Bt棉和常规棉的花蕊饲喂 ,取食Bt棉花粉的蛾子的产卵量、卵孵化率较取食常规棉花粉的下降 49.2 %、6 4.4%。在Bt棉上棉铃虫幼虫取食次数明显减少 ,吐丝下垂次数是常规棉上幼虫的 3.4倍。Bt棉上棉铃虫幼虫分布在后期与常规棉有差异 ,在花上的幼虫显著多于常规棉。棉铃虫中等以下发生时 ,Bt棉对产卵有明显的排趋性 ,大发生时无排趋性。

Effect on the biological habit of ballworm after planting Bt transgenic cotton in Xinjiang

In this paper,we suystenatically studied the effect on the biological habit of ballworm after planting Bt transgenic cotton ,results showed ,when Bt cotton was taken by elder larva of ballworm ,the pupate rate declined 33.3%～51.7%,emergence rate declined 26.3%～57.8%,pupa weight reduced 6.5%～11.4%,it had little effect on pupal period;the amount of oviposition of the fifth star larva declined 43.4%～67.8%,hatching rate declined 77.1%～84.5%.Feeding moth which just finished emergence with stylar of Bt cotton(a) and non-transgenic cotton(b)separatedly,the amount of oviposition and hatching rate of (a)moth were declined 49.2% and 64.4% than(b).The trophic frequence of the larva on Bt cotton obviously declined,frequence of fusule drop was 3.4 times compared with the control,the amoumt of larva on flower of Bt cotton were significantly more than control.