不同环境温度下大草蛉对黄精主要害虫二斑叶螨的控害潜能评估

Potential management capacity investigation of Chrysopa pallens(Hymenopter:Chrysopidae) to Tetranychus urticae(Acarina:Tetranychidae) on the host plant sealwort in different environmental temperatures

以重要中草药黄精Polygonattum sibiricium的主要害虫二斑叶螨Tetranychus urticae为研究对象,在5个温度(15℃、20℃、25℃、30℃及35℃)条件下,测定了大草蛉Chrysopa pallens雌成虫对二斑叶螨的捕食功能反应及搜索效应。试验结果表明,在温度处理设置范围内,各温度下大草蛉对二斑叶螨的捕食功能反应均拟合HollingII功能反应模型。大草蛉对二斑叶螨的捕食,受温度及猎物密度影响显著。而在各温度处理间,以25℃下的瞬间攻击率最大为0.664,而猎物处理时间最短为0.025d。瞬间攻击率在高温及低温条件下均低于25℃。但猎物处理时间则呈显出相反的趋势。基于捕食功能反应结果计算的搜索效应表明,大草蛉对二斑叶螨的搜索效应在各温度处理内随猎物密度增加而线性上升,其中以25℃下的捕食效应最高,而在15℃下的最低。本研究结果表明,大草蛉雌成虫作为一种捕食性天敌,对黄精上的二斑叶螨具有一定的控害潜能,并且其取食能力受环境温度影响显著。

We executed present experiments with Tetranychus urticae as primary target on the host plant sealwort to test the predatory functional response and searching efficiency of Chrysopa pallens female adult under 5 different temperatures（15℃,20℃,25℃,30℃ and 35℃）.The results showed that the predatory tendencies of C.pallens to T.urticae were all fitted Holling II modeling in all temperature treatments.The temperature and prey density both influenced the prey consumed amount significantly.The parameters of Holling modeling,the instant attack rate was highest in the treatment of 25℃ and decreased with the temperature increasing or reducing.The handling time of each prey was the lowest in the treatment of 25℃ and showed opposite tendency to the attack rate.We calculated the search efficiency index of C.pallens by the parameter of Holling model and showed high linear increasing of search efficiency with the augment of prey density in all temperature treatments.Among them,the search efficiency in 25℃ was the highest and in 15℃ was the lowest.According with the indication of present study,as an efficacious predatory natural enemy,the C.pallens showed extremely high potential capacity to the management of T.urticae on sealwort and the net predatory capacity could be influenced by temperature significantly.