龟纹瓢虫成虫对3种害虫的捕食作用

Predation functional response of Propylea japonica adults to three kinds of pests

为明确天敌昆虫龟纹瓢虫Propylea japonica对3种害虫莲缢管蚜Rhopalosiphum nymphaeae、紫薇长斑蚜Sarucallis kahawaluokalani和红带滑胸针蓟马Selenothrips rubrocinctus的捕食效应,分别在室内测定了龟纹瓢虫成虫对莲缢管蚜3~4龄若蚜、紫薇长斑蚜3~4龄若蚜和红带滑胸针蓟马2~3龄若虫的捕食作用。结果表明:龟纹瓢虫成虫对3种害虫的捕食效果可用Holling-Ⅱ模型进行拟合,对红带滑胸针蓟马2~3龄若虫的捕食能力最强,为192.14,对莲缢管蚜的捕食能力最弱,为91.12。龟纹瓢虫成虫对莲缢管蚜、紫薇长斑蚜和红带滑胸针蓟马的寻找效应呈线性相关,猎物密度越大寻找效应越低。龟纹瓢虫成虫对3种害虫的最佳搜寻密度分别为48.35、23.48和36.48头。由此可知,龟纹瓢虫对莲缢管蚜、紫薇长斑蚜和红带滑胸针蓟马具有一定的控害作用。

To study the predation by Propylea japonica adults on Rhopalosiphum nymphaeae,Sarucallis kahawaluokalani and Selenothrips rubrocinctus,predation of P.japonica on 3 rd~4 th instar R.nymphaeae and S.kahawaluokalani,2 nd~3 rd instar of S.rubrocinctus were investigated in laboratory.The study indicated that functional response of adult P.japonica to the three kinds of pests could be fitted by Holling-Ⅱmodel.P.japonica has the strongest predation capacity to the S.rubrocinctus which was 192.14,and the weakest predation capacity to R.nymphaeae which was 91.12.There was a Linear correlation between searching efficiency of P.japonica adults on R.nymphaeae,S.kahawaluokalani and S.rubrocinctus,the higher prey density,the lower of searching efficiency.The best searching densities of adult P.japonica for the three kinds pests were 48.35,23.48 and 36.48 respectively.The study showed that P.japonica has the potential to be predator of R.nymphaeae,S.kahawaluokalani and S.rubrocinctus.