大草蛉幼虫对不同寄主植物上烟粉虱卵的捕食功能反应与搜寻效应
The predatory functional response and searching effect of Chrysopa pallens larvae to Bemisia tabaci eggs on different host plants

为了研究不同寄主上大草蛉Chrysopa pallens (Rambur)幼虫对烟粉虱Bemisia tabaci(Gennadius)卵的捕食功能反应与搜寻效应,在室内条件下评估了大草蛉捕食功能反应模型,并研究了大草蛉3龄幼虫对棉花、烟草和辣椒上烟粉虱卵的搜寻效应和控害潜能.结果显示,在3种寄主植物上大草蛉3龄幼虫捕食量均随猎物密度的增加而升高,在烟草、棉花、辣椒上的捕食量分别为7.6~28.4、5.4~23.2、6.0~18.8粒;3种寄主植物上的大草蛉捕食功能反应均拟合Holling II、III功能反应模型;在烟草上大草蛉的瞬间攻击率最大,为0.470,处理时间最短,为0.021;在3种寄主植物上大草蛉3龄幼虫搜寻效应均随猎物密度的增加而下降,当猎物密度相同时,在烟草上的搜寻效应高于棉花和辣椒.研究表明,不同寄主植物能够影响大草蛉3龄幼虫对烟粉虱卵的瞬间攻击率及其搜寻效应.
To clarify the predatory functional response and searching effect of Chrysopa pallens larvae to Bemisia tabaci eggs on different host plants, the functional response model was evaluated in the laboratory, and the searching effects and control potentials of C. pallens against B. tabaci were studied on three host plants, including Nicotiana tabacum, Gossypium hirsutum and Capsicum annuum. The results showed that the predatory capacities of C. pallens larvae to B. tabaci eggs on three host plants enhanced with increasing prey density. The predatory capacities of C. pallens 3rd-instar larvae on N.tabacum, G.hirsutum and C.annuum were 7.6-28.4, 5.4-23.2 and 6.0-18.8, respectively. The functional response of C. pallens 3rd-instar larvae on B. tabaci eggs on three host plants fitted to Holling II & III formula. The instantaneous attacking rate on N. tabacum was 0.470, higher than that on the other hosts. The handling time on N. tabacum was 0.021, shorter than that on others. The searching effects on three host plants decreased with increasing prey density, and N. tabacum showed the larger drop than the other hosts under the same prey density. The results indicated that different host plants could affect both instantaneous attacking rate and searching effect of C. pallens 3rd-instar larvae on B. tabaci eggs.