七星瓢虫成虫对烟蚜的捕食作用

对七星瓢虫CoccinellaseptempunctataL .成虫对烟蚜Myzuspersicae的捕食作用进行了定量研究。七星瓢虫成虫对烟蚜的功能反应属HollingⅡ型反应 ,拟合的圆盘方程为Na =1 .1 5 76Nt ( 1 +0 .0 0 3 48Nt) ,χ2 检验表明圆盘方程理论值与实测值相符。捕食选择试验表明在烟蚜、烟青虫Helicoverpaassaut(Guenee)卵和 1龄幼虫 3种猎物中 ,七星瓢虫成虫最喜好烟蚜。七星瓢虫成虫对自身密度的功能反应用Watt模型拟合为A =2 90 .0 3P-0 .7584,其捕食作用率与个体间相互干扰作用的关系用Hassell模型拟合为E =0 .8783 7P-0 .1 0 0 94。文中进一步就烟田中七星瓢虫的保护利用进行了讨论。

Predation of Myzus persicae by adults of Coccinella septempunctata

Predation of Coccinella septempunctata L. on Myzus persicae (Sulzer) was quantitatively investigated in the laboratory. The functional response of adult C. septempunctata to M. persicae could be described by Holling Ⅱ model; the fitted Holling disc equation was Na=1.1576Nt/(1+0.00348Nt), χ 2 test showed that the theoretical expectation calculated by the fitted Holling disc equation fitted well with the observed value. The predation selectivity experiment revealed that adult C. septempunctata preferred M. persicae among three preys of M. persicae , eggs and larvae of Helicoverpa assaulta. The functional response of adult C. septempunctata to the density of itself could be fitted with Watt model, A=290.03P -0.7584 ; while the relationship between predation efficiency and individual interafervence could be fitted with Hassell model, E=0.87837P -0.10094 . Based on the current experiments, conservation and utilization of C. septempunctata in tobacco fields was further discussed.