二星瓢虫的捕食选择性及对枸杞棉蚜的捕食功能

Study on the predation selectivity and function of Adalia bipunctata L.on Aphis gossypii Glover.

为了解二星瓢虫对枸杞棉蚜和枸杞木虱的捕食偏好性,在不同棉蚜、瓢虫密度及相同的瓢蚜比条件下,探究二星瓢虫各龄期幼虫和成虫的捕食量、寻找效应、种内干扰及捕食者密度对其捕食活动的影响。结果表明:二星瓢虫各龄期幼虫及成虫捕食枸杞棉蚜的功能反应均符合Holling-Ⅱ模型,二星瓢虫的种内干扰和虫口密度对其捕食枸杞棉蚜数量的影响分别符合Hassell模型和Watt模型。二星瓢虫1、2、3、4龄期幼虫及成虫日最大理论捕食量分别为13.19、29.29、62.89、124.67和105.03头;在一定空间内,二星瓢虫个体间存在一定的种内干扰效应,1龄幼虫受到的干扰最大,干扰常数为1.1734;二星瓢虫的密度会对自身的捕食活动产生一定影响,4龄幼虫对食物的竞争最激烈,竞争参数为0.9220。研究结果可为改进二星瓢虫的人工养殖技术、提高瓢虫资源的利用效率及防控效果提供数据参考。

In order to explore the predation preferences of Adalia bipunctata L.on Aphis gossypii Glover.and Poratrioza sinica Yang et Li,the effects of predation amounts,searching efficiency,in-traspecific interference and predator density on the predation activities of Adalia bipunctata L.larvae at different stages and adults are investigated under different densities of Aphis gossypii Glover.and Adalia bipunctata L.,as well as the same ratio of Adalia bipunctata L.to Aphis gossypii Glover.The results show that the functional responses of Adalia bipunctata L.larvae at different stages and adults to Aphis gossypii Glover.are consistent with the Holling-Ⅱmodel.The effects of intraspecific inter-ference and population density of Adalia bipunctata L.on its predation of Aphis gossypii Glover.con-form to the Hassell model and Watt model respectively.The maximum theoretical daily predation amounts of the 1st,2nd,3rd and 4th instar Adalia bipunctata L.larvae and adults are 13.19,29.29,62.89,124.67 and 105.03 Aphis gossypii Glover.respectively.There exists intraspecific interference effects among individuals of Adalia bipunctata L.within a certain space.Besides,the 1st instar larva is the most affected with an interference constant of 1.1734.The density of Adalia bipunctata L.will have a certain impact on its predatory activity.The 4th instar larva has the most intense competition for food with a competition parameter of 0.9220.The research results can provide data reference for improving the artificial breeding technology of Adalia bipunctata L.and the utilization efficiency of its resources as well as the prevention and control effects.