棉田使用氰戊菊酯与棉蚜再猖獗

氰戊菊酯的复配剂－丰收菊酯，对棉田天敌和棉蚜均有极强的杀伤力，从而同时将它们降到低水平上，蚜量显著小于对照。对照区没有药剂的控蚜作用，但在于敌作用下，蚜量上升后又下降，没能形成很大的群体。由于抗药性的发展，氰戊菊酯已不能控制棉蚜数量，又对棉田主要天敌有极强的杀伤力，以致使用后棉蚜在不能被药剂杀死的同时也推动了天敌的控制，造成再猖獗。

THE RESURGENCE OF THE COTTON APHID (APHIS GOSSYPII GLOVER) AFTER USING FENVALERATE

In the plot where water was sprayed, no insecticide killed cotton aphid, but the enemies of the aphid could control the pest very well, so no large population of the aphid could be formed, FENGSHOU-JUZHI, a binary comination of fenvalerate and monocrotophos, could kill the enemies, but it killed the taphid more, so the amount of the pest was least of the three ireatments, Because, of the development of the resistance, the effectiveness of fenvalerate, a good aphicide in the early of 1980's, wasweak to the aphid now.On the contrary,it killed the enemies largely.When fenvalerate was sprayed in the plot, the aphids were killed only a few and no enemies could control the pest at the same time, which caused the resurgene of the aphid,