转基因棉和常规棉叶片对抗Cry1Ac近等基因系棉铃虫生长发育的影响

利用室内饲喂法,以抗Cry1Ac近等基因系棉铃虫为材料,比较转基因棉花33B和SGK321及其对照亲本DP5415和石远321对抗、感棉铃虫生长发育的影响。结果表明,抗性棉铃虫在取食常规棉叶后表现出一定的适合度代价。取食DP5415和石远321两种常规棉花后,抗性品系棉铃虫的幼虫存活率显著低于敏感品系,取食33B和SGK321两种转基因棉花的抗性棉铃虫,不仅其幼虫存活率显著高于敏感品系,而且致死中时间也比敏感品系延长。取食9天后,抗性品系在常规棉花石远321和DP5415上发育到3龄和4龄幼虫的比例显著低于敏感品系,取食33B和SGK321转基因棉花的抗性品系发育到3龄幼虫的比例均显著高于敏感品系。抗性品系在常规棉上的蛹重均显著低于敏感品系,部分取食转基因棉花的抗性品系棉铃虫可以化蛹,而敏感品系不能在转基因棉花上化蛹。

Effects of transgenic and conventional cotton leaves on the growth and development of resistant to Cry1Ac near-isogenic Helicoverpa armigera

By using indoor cotton leaf rearing, the effects of transgenic cotton on the growth and development of near-isogenic Helicoverpa armigera (Hübner) resistant to Cry1Ac was compared with susceptible strain in the laboratory. This study demonstrates that resistant strain indicates fitness costs when feeding on conventional cotton leaves. The larval survival rates of resistant strain were significantly lower than those of susceptible strain feeding on non-transgenic cotton (conventional parental cotton) DP5415 and Shiyuan321. However, when resistant Helicoverpa armigera fed on transgenic cottons (33B and SGK321), not only the larval survival rates were obviously higher than those of susceptible strain, but also its LT₅₀s were extended than those of the latter. After feeding 9 days, the percentages of 4^th and 3^rd instar larvae of resistant strain fed on DP5415 and Shiyuan321 were significantly lower than those of susceptible strain, while the percentages of 3^rd instar larvae of resistant strain were obviously higher than those of susceptible strain when they fed on 33B and SGK321. The pupal weights of resistant strain fed on conventional cottons were significantly lower than susceptible strain. Parts of resistant H.armigera could pupate after they fed on transgenic cotton, but there were no larvae could survive up to pupae in susceptible strain.