拟环纹豹蛛对斜纹夜蛾卵及幼虫的捕食效应

Predatory efficiencies of Pardosa pseudoannulata on eggs and larvae of Spodoptera litura

实验室条件下研究了拟环纹豹蛛对斜纹夜蛾卵和幼虫的捕食效应。结果表明,拟环纹豹蛛极少捕食斜纹夜蛾卵,斜纹夜蛾卵供捕食处理后孵化率与对照差异不显著;拟环纹豹蛛对斜纹夜蛾1龄和2龄幼虫的捕食量明显高于3龄幼虫,1d内对1龄和2龄幼虫的捕食量分别为38.20和24.60头,3d内对3龄幼虫的捕食量为5.50头。拟环纹豹蛛对斜纹夜蛾2龄幼虫的捕食功能反应符合HollingⅡ型,雌雄蛛的功能反应模型方程分别为Na=1.2577N/(1+0.0123N)和Na=1.3503N/(1+0.0189N),捕食上限1/Th分别达102和71头;拟合HollingⅢ新模型得最佳寻找密度b为24～29头。

The predatory efficiencies of Pardosa pseudoannulata （ Boesenberg et Strand） on eggs and lar- vae of Spodoptera litura （Fabriciu） were tested in laboratory condition. Results showed that the eggs of S. litura were seldom preyed by P. pseudoannulata, and the hatch rate of eggs of preying treatment showed no significant difference with which of control. The predatory capacity of P. pseudoannulata on first or second instar larvae was stronger than that on third instar larvae, with individuals of 1 st and 2na in- star larvae killed by P. pseudoannulata was 38.20 and 24.60 respectively for 1 day, while individuals of 3^rd instar larvae killed was 5.50 for 3 days. The predatory functional response of P. pseudoannulata on 2na instar larvae matched with Holling H model, which was Na = 1. 2577N/ （ 1 ＋ 0. 0123N） for female, and Na = 1. 3503N/ （1 ＋0. 0189N） for male, and the maximal preying quantity was 102 and 71 respec- tively. When fitting to new model of Holling Ⅲ, the best searching density was 24 -29.