侧刺蝽对草地贪夜蛾的捕食行为和捕食能力

Predation of Spodoptera frugiperda Larvae by Andalusia spinidens(Fabricius)Nymphs

为明确侧刺蝽对重大入侵害虫草地贪夜蛾的控害潜能,本研究测定了侧刺蝽若虫对草地贪夜蛾幼虫的捕食能力及其功能反应,观察并总结了其捕食行为特点。结果表明,侧刺蝽4龄和5龄若虫对草地贪夜蛾3~5龄幼虫均具有较强的捕食能力。侧刺蝽5龄若虫日均捕食草地贪夜蛾3龄幼虫8.30头,4龄幼虫6.33头,5龄幼虫3.80头,5龄若虫对草地贪夜蛾3龄幼虫的捕食量最高;侧刺蝽4龄若虫对草地贪夜蛾3龄和4龄幼虫日均捕食量分别为4.67头和2.93头;侧刺蝽3龄若虫仅对草地贪夜蛾3龄幼虫有较强的捕食能力,日均捕食量为3.50头。侧刺蝽若虫对草地贪夜蛾幼虫不同龄期的捕食量随猎物密度增加逐渐升高后趋于稳定,符合HollingⅡ功能反应模型。侧刺蝽5龄若虫对草地贪夜蛾的搜寻能力、处理时间及日最大捕食量均显著优于3龄若虫,控害效能更强。本研究结果为利用侧刺蝽控制草地贪夜蛾提供了重要参考依据。

The control potential of the new natural enemy Andalusia spinidens to the invasive pest Spodoptera frugiperda was assessed by measuring the predation ability and functional responses of A.spinidens nymphs to S.frugiperda larvae and observing predatory behaviors.The results showed that the 4th and 5th instar nymphs of the predator exhibited strong predatory ability on the 3rd―5th instar larvae of S.frugiperda.Daily predation amount of the 5th instar nymphs on the 3rd,4th,and 5th instar larvae was 8.30,6.33,and 3.80,and the highest predation of 5th instar nymphs on 3rd instar larvae.For the 4th instar nymphs on the 3rd and 4th instar larvae,it was 4.67 and 2.93,respectively.In contrast,the 3rd instar nymphs had weak predatory ability,only showing relatively strong predation on the 3rd instar larvae,with an average daily predation amount of 3.50.The predation of the nymphs on different instars S.frugiperda increased gradually with the increase of prey density and then stabilized,which fits well with the HollingⅡfunctional response model.The searching ability,processing time and daily maximum predation of the 5th instar nymphs on S.frugiperda were superior to those of the 3rd instar nymphs,and the control efficiency of the 5th instar nymphs was higher.The results serve as an important reference for using the predatory bugs in control of S.frugiperda.