黄玛草蛉对两种蚜虫的捕食效能

实验室条件下研究了黄玛草蛉2龄与3龄幼虫对甘蓝蚜以及玉米蚜成虫的捕食功能反应。结果表明:黄玛草蛉2龄与3龄幼虫对2种蚜虫的捕食量均随着猎物密度的增加而增加,寻找效应随着猎物密度的增加而减小。不同龄期幼虫对2种蚜虫的捕食功能反应均符合HollingⅡ模型,黄玛草蛉2龄与3龄幼虫对玉米蚜最大理论日捕食量分别为120.48头、185.18头;黄玛草蛉2龄与3龄幼虫对甘蓝蚜最大理论日捕食量分别为60.60头、86.95头。在相同猎物种类下,黄玛草蛉3龄幼虫对2种蚜虫的捕食量均高于黄玛草蛉2龄幼虫;在相同猎物密度下,黄玛草蛉2龄幼虫与3龄幼虫对玉米蚜的捕食量均高于甘蓝蚜。

Function response of Mallada basalis (Walker) on Brevicoryne brassicae (L.) and Rhopalosiphum maidis (Fitch)

The predatory capacity of the 2 nd and the 3 rd instar larvae of Mallada basalis(Walker)to the adults of Brevicoryne brassicae(L.)and Rhopalosiphum maidis(Fitch)were explored in the laboratory.Results showed that the daily predatory amount of the 2 nd and the 3 rd instar larvae of M.basalis to B.brassicae and R.maidis increased with the increase of prey density.While the searching rate of M.basalis larvae decreased with the increase of prey density.The functional responses of M.basalis larvae in different developmental stages to the two prey species fitted well with HollingⅡmodel.The maximum daily amount of R.maidis adults consumed by the 2 nd and the 3 rd instar larvae of M.basalis were 120.48 and 185.18,respectively.The maximum daily amount of B.brassicae adults consumed by the 2 nd and the 3 rd instar larvae of M.basalis were 60.6 and 86.95,respectively.When provided with the same prey individuals,the daily predatory amount of the 3 rd instar larvae of M.basalis to R.maidis and B.brassicae were higher than that of the 2 nd instar larvae of M.basalis.While the daily predatory amount of the 2 nd and 3 rd instar larvae of M.basalis to R.maidis were higher than that to B.brassicae.