叉角厉蝽不同龄期和不同释放方式对烤烟斜纹夜蛾防治效果研究初报

Preliminary Study on Control Effect of Different Ages and Release Modes of Eocanthecona furcellata on Spodoptera litura in Flue-cured Tobacco

开展了不同龄期(虫卵、3~4龄若虫,成虫)叉角厉蝽在不同释放方式下(网罩释放、无网罩释放)对烤烟斜纹夜蛾防治的大田试验,研究了叉角厉蝽对烤烟斜纹夜蛾的防治效果。结果表明:相同虫龄的叉角厉蝽网罩释放防治效果优于无网罩释放的,叉角厉蝽3~4龄若虫和成虫对斜纹夜蛾有明显的捕食能力,防治效果依次为3~4龄若虫>成虫>虫卵;网罩释放叉角厉蝽3~4龄若虫后斜纹夜蛾虫口减退率为83.75%,对烤烟斜纹夜蛾的防治效果达到87.13%;与对照比较,烟叶产量和产值分别增加了374.2 kg/hm2、4500元/hm2,上等烟比例提高了13个百分点,差异显著、效益明显。研究表明,烤烟大田释放3~4龄若虫叉角厉蝽225~300头/hm2防治烤烟斜纹夜蛾是可行的。

In order to study the control effect of Eocanthecona furcellata on Spodoptera litura in flue-cured tobacco,a field experiment was conducted to control flue-cured tobacco Spodoptera litura at different ages(eggs,3rd-4th instar nymphs,adults)by different release methods(net release and no net release).The results showed that the control effect of Eocanthecona furcellata with net release was better than that without net release at the same insect age.The 3rd-4th instar nymphs and adults of Eocanthecona furcellata had obvious predation ability to Spodoptera litura,and the order of control effect was 3rd-4th instar nymphs>adults>eggs.The population decline rate of Eocanthecona furcellata with the 3rd-4th instar nymphs and net release on Spodoptera litura was 83.75%,and the control effect of Spodoptera litura of flue-cured tobacco was 87.13%.Compared with the control,the yield and output value of tobacco leaves increased by 375 kg/hm2 and 4500 yuan/hm2,respectively,and the proportion of top-grade tobacco increased by 13 percentage points,with significant difference and obvious benefit.Therefore,it was feasible to control Spodoptera litura by releasing 225~300 nymphs/hm2 and 3rd-4th instar Eocanthecona furcellata in flue-cured tobacco field.