条纹蝇虎对灰茶尺蠖幼虫的捕食作用

为明确条纹蝇虎（Plexippus setipes）对灰茶尺蠖（Ectropis grisescens）的防控效果,在室内条件下,开展了条纹蝇虎对灰茶尺蠖幼虫的捕食量、捕食功能反应、捕食选择性和种内干扰效应的研究。结果显示,条纹蝇虎偏好捕食灰茶尺蠖低龄幼虫,不同发育阶段捕食能力存在显著差异;其中成蛛捕食能力最强,日均可捕食灰茶尺蠖1龄幼虫17.44头,幼蛛捕食能力相对较弱,日均捕食1龄幼虫2.33头。条纹蝇虎捕食功能反应符合Holling Ⅱ模型,捕食量随灰茶尺蠖幼虫密度的增加而增加,而搜寻效应逐渐降低。捕食选择性试验表明,条纹蝇虎对灰茶尺蠖1龄幼虫和2龄幼虫表现为正喜好性（Ci>0）,对3龄幼虫表现为负喜好性（Ci<0）。条纹蝇虎对灰茶尺蠖幼虫的捕食作用同时受自身密度的影响,存在较强的种内干扰反应,该反应符合Hasse Ⅱ模型。研究表明,条纹蝇虎对灰茶尺蠖幼虫具有较强的捕食能力和良好的防控潜能,这为利用茶园蜘蛛天敌资源提供理论依据。

Predation of Plexippus setipes on Ectropis grisescens Larvae

To clarify the control potential of Plexippus setipes on Ectropis grisescens, studies about the predator functional response, predation selectivity and intraspecific competition of P. setipes on E. grisescens larvae were conducted under indoor conditions. The results show that the P. setipes preferred to feed on the early stage larvae of the E. grisescens. There were significant differences in the predation ability among different developmental stages of P. setipes. Specifically, the adult spider had the strongest predation ability to hunt 17.44 larvae per day of the first instar of the E. grisescens, while the juvenile spider had relatively weak predation ability with only a daily of 2.33 larvae of the first instar. The predator functional response of P. setipes was in accordance with the Holling Ⅱ model. The Searching efficiency of P. setipes decreased with the increase of E. grisescens population. The predation selectivity shows that P. setipes showed positive preference (Ci > 0) for 1^st and 2^nd instar E. grisescens larvae along with negative preference (Ci < 0) for 3^rd instar larvae. The predatory effect of P. setipes on E. grisescens larvae was also influenced by their own population density. There was a strong intraspecific competition, which was consistent with the Hasse Ⅱ model. This study indicates that P. setipes had a strong predatory ability and control potential on E. grisescens larvae, providing a theoretical basis for exploring the use of spiders in tea plantations.