异色瓢虫和七星瓢虫对核桃黑斑蚜捕食能力比较

Harmonia axyridis and Coccinella septempunctata:Predation Comparison to Chromaphis juglandicola

异色瓢虫(Harmonia axyridis)和七星瓢虫(Coccinella septempunctata)是核桃黑斑蚜(Chromaphis Juglandicola)的重要捕食性天敌,为了评价2种瓢虫对核桃黑斑蚜的捕食能力,室内条件下测定了异色瓢虫和七星瓢虫对不同密度核桃黑斑蚜的捕食量。结果表明:异色瓢虫和七星瓢虫对核桃黑斑蚜的捕食功能反应均符合Holling-Ⅱ型圆盘方程。2种瓢虫对核桃黑斑蚜的日最大捕食量:异色瓢虫>七星瓢虫,分别为490.1961头/d和387.5969头/d,瞬时攻击率:异色瓢虫>七星瓢虫,分别为1.0034和0.9218,处理时间:异色瓢虫<七星瓢虫,分别为0.0020 d和0.0026 d。2种瓢虫对核桃黑斑蚜的寻找效应均随猎物密度的增加而降低,且异色瓢虫的寻找效应高于七星瓢虫。Holling-Ⅲ型功能反应新模型拟合得出,单头异色瓢虫和七星瓢虫的最佳寻找密度分别为149.4104头和147.9904头。异色瓢虫和七星瓢虫对核桃黑斑蚜均具有较强的捕食能力,且异色瓢虫捕食能力强于七星瓢虫。

Harmonia axyridis and Coccinella septempunctata are important predators of Chromaphis juglandicola.To evaluate the predation ability of H.axyridis and C.septempunctata adults to C.juglandicola,the predation number of H.axyridis and C.septempunctata to C.juglandicola were determined in laboratory.The results showed that the functional responses of H.axyridis and C.septempunctata to C.juglandicola fitted well with the Holling-Ⅱequation.The daily maximum predation number of H.axyridis was higher than that of C.septempunctata,which was 490.1961 and 387.5969,respectively.The instantaneous attack rate of H.axyridis was higher than that of C.septempunctata,which was 1.0034 and 0.9218,respectively.The handling time of H.axyridis was shorter than that of C.septempunctata,which was 0.0020 d and 0.0026 d,respectively.The searching efficiency of H.axyridis and C.septempunctata decreased with the increase of prey density,and the searching efficiency of H.axyridis was higher than that of C.septempunctata.The optimal searching density of H.axyridis and C.septempunctata was 149.4104 and 147.9904 pests per predator according to Holling-Ⅲmodel.The results indicate that H.axyridis and C.septempunctata adult are efficient for the control of C.juglandicola,and the predatory capacity of H.axyridis is higher than that of C.septempunctata.