取食转Bt基因棉花上的棉蚜对丽草蛉发育和繁殖的影响

为明确转Bt基因抗虫棉对捕食性天敌的生态效应 ,比较了 2种转Bt基因抗虫棉 (GK-1 2和新棉99B)和 1种常规棉上的棉蚜Chrysopaformosa对丽草蛉Aphisgossypii发育和繁殖的影响。结果表明 ,(1 )与取食常规棉泗棉 3号上棉蚜的对照相比 ,取食转Bt基因抗虫棉GK- 1 2上棉蚜的第 1代和第 2代丽草蛉 ,其幼虫期和茧期的死亡率、幼虫和茧的发育历期、茧重及成虫性比等均与对照无显著差异 ;但第 1代成虫的产卵量减少了 2 88 0粒 ,与对照差异显著 (P <0 . 0 1 ) ;第 2代成虫所产卵的孵化率为 64. 0 % ,显著低于对照的 77. 7% (P <0 0 1 )。 (2 ) 2个品种的Bt棉对丽草蛉发育和繁殖的影响也略有差异。与取食GK 1 2上棉蚜的个体相比 ,取食新棉 99B上蚜虫的第 1代丽草蛉 ,其幼虫发育历期缩短了 0 . 6d(P <0 0 1 ) ,茧期缩短了 0 . 7d(P <0 . 0 1 ) ,茧重降低了 1 . 2mg(P <0 .0 1 ) ,幼虫期和茧期的死亡率、茧重以及成虫性比等则无显著差异 ;雌成虫产卵前期、产卵期、产卵量和寿命等繁殖学特性也无显著差异 ,但其成虫所产卵的孵化率为 65. 0 % ,显著低于取食GK- 1 2上棉蚜的处理 (72 . 7% ,P <0. 0 1 )。分别取食 2种Bt棉上的棉蚜 ,对第 2代丽草蛉的发育和繁殖的影响差异则较小。

Survival, development and fecundity of Chrysopa formosa feeding on Aphis gossypii propagated on transgenic Bt cotton

Laboratory feeding experiments using transgenic Bt cotton lines GK12 and NuCOTN 99B were carried out to study the impacts on Bt-fed herbivore, cotton aphid Aphis gossypii Glover, on non-target predator, green lacewing Chrysopa formosa Brauer,with the parental line of GK12, non-transgenic Simian-3 as the control. The mortality and development during immature period, cocoon body mass, adult sex ratio and fecundity, and egg viability of C. formosa were measured during the two generations' rearing. The results showed that: (1) Compared to the control, aphid on GK12 had no significant impacts on immature survival and development and adult sex ratio of C. formosa for both generations. But the number of eggs laid per female of the first generation averaged 475.9, which was much lower than that of the control (763.9 eggs per female, P<0.01). The egg viability of the second generation was 64.0%, which was also much lower than that of the control (77.7%, P<0.01). (2) Compared to GK12, NuCOTN 99B had slightly different impacts on the first generation of C. formosa. Larval stage shortened 0.6?d (P<0.01), cocoon stage shortened 0.7?d (P<0.01), cocoon body mass decreased 1.2?mg (P<0.01), and egg viability dropped to 65.0% (P<0.01, that of GK12 treatment, 72.7%). But other biological parameters, such as immature survival, adult sex ratio, oviposition capacity, etc., didn't differ. Such differences didn't occur in the second generation of C. formosa.