七星瓢虫对豆蚜的功能反应

［目的］测定七星瓢虫各虫态对豆蚜的捕食能力。［方法］将野外七星瓢虫(Coccinella septempunctata L.)采回并在室内饲养一代后，就其各龄幼虫及雌雄成虫对豆蚜(Aphis craccivora Koch)的捕食能力进行室内测定。［结果］ 七星瓢虫各龄期幼虫以及雌雄成虫对豆蚜的功能反应均属HollingⅡ型模型，1、2、3、4龄幼虫捕食反应拟合的圆盘方程分别为Na=1.121 86N/(1+0.059 92N)、Na=1.217 04N/(1+0.049 33N)、 Na=0.789 92N/〖JP2〗(1+0.008 00N)、Na=0.967 01N/(1+0.001 41N)，雌、雄成虫的圆盘方程分别为Na=0.958 64N/(1+0.001 03N)、Na=0.976 20N/(1+0.001 52N)，经χ2检验各虫态的捕食反应的圆盘方程理论值与实测值相符。用七星瓢虫雌成虫进行自身密度的干扰反应测定，利用Hassell模型进行拟合，所得模型方程为E=0.447 4P-0.433 7，经χ2检验雌成虫的捕食作用率实测值与理论值相符，该模型方程能很好地反映雌成虫自身密度的干扰程度。［结论］ 1～4龄幼虫、雄成虫和雌成虫对豆蚜的日最大捕食量分别为18.7、24.7、98.8、685.5、642.5、927.5头。

Functional response of Coccinella septempunctata to Aphis craccivora

［Objective］To test the predation ability of Coccinella septempunctata L. of different stages to Aphis craccivora Koch.［Method］ Predation of C. septempunctata to varying densities of A. craccivora feeding on Vicia faba L. was examined under laboratory conditions. All stages of C. septempunctata were isolated individually with different prey densities at (25±1)℃ and a photoperiod of 16L〖DK1〗∶8D (h). ［Result］ All stages of C. septempunctata showed a functional response of HollingⅡ model: Na=1.121 86N/(1+0.059 92N) for the 1st instar larvae; Na=1.217 04N/(1+0.049 33N) for the 2nd instar larvae; Na=0.789 92N/(1+0.008 00N) for the 3rd instar larvae; Na=0.967 01N/(1+0.001 41N) for the 4th instar larvae; Na=0.958 64N/(1+0.001 03N) for the female adults, and Na=0.976 20N/(1+0.001 52N) for the male adults. The relationships between the quantity of A. craccivora preyed by seven spotted ladybeetles and the density of A. craccivora could be represented by a negative accelerative curve. The ladybeetle individuals interfered each other. The Hassell model could reflect their functional responses. The interference equation was E=0.447 4P-0.433 7. ［Conclusion］ The estimated maximum of aphids predated by 1st to 4th instar larvae and the adult females and males of seven spotted ladybeetles per day were 18.7, 24.7, 98.8, 685.5, 642.5 and 927.5, respectively.