不同寄主对棉大卷叶螟第4代种群增长的影响

 以转基因棉花品种国抗22、中抗310及其常规非转基因亲本泗棉3号、苏棉12为材料，以野生寄主苘麻为对照，以生命表形式研究这5种寄主对棉大卷叶螟种群增长的影响。结果表明：取食转基因棉花品种国抗22、中抗310叶片的棉大卷叶螟室内种群不能完成1个世代，在低龄幼虫时就全部死亡，自然种群趋势指数分别为0.08和0.01，远远小于1；取食野生寄主苘麻的幼虫发育最快，5个虫龄的累计存活率达到52.8%，均高于2个常规棉花品种泗棉3号（48.2%）和苏棉12（37.3%），同时雌成虫寿命和产卵持续期长，雌性比率超过50%，显示出较大的生殖潜能；泗棉3号和苏棉12上棉大卷叶螟的自然种群趋势指数分别是1.61和1.12，表明棉大卷叶螟种群在这2个品种棉田呈增长态势。研究表明，2个转基因棉花品种国抗22、中抗310的大面积推广不会加重棉大卷叶螟的危害，如果没有外来虫源的不断补充，转基因棉田的棉大卷叶螟种群数量将不可能大幅度增长。

Effect of Different Hosts on Population Increase of the Forth Generation of Sylepta derogata

Using transgenic cotton varieties GK22,ZK310 and their corresponding non-transgenic parents Simian 3,Sumian 12,respectively,and a wild host plant Abutilon theophrasti Medicus of S.derogata,influence of population dynamics of S.derogata fed on five host plants were studied by constructing life table.The results showed S.derogata could not complete a whole generation fed on leaves of transgenic cotton varieties GK22 or ZK310,and the larvae all died in low instars,and natural population trend index(I) were 0.0...