多物种共存系统中3种蜘蛛对褐飞虱的控制作用

选择稻田生态系统中天敌蜘蛛优势种食虫沟瘤蛛（Oedothorox insecticeps)、拟水狼蛛（Pirata subpiraticus)、粽管巢蛛（Clubiona japonicola)和水稻主要害虫飞虱（Nilaparvata lugenis)组成多物种共存系统，运用二次通用旋转组合设计统计方法探讨多种蜘蛛对1种稻虫的控制作用，分析天敌之间以及天敌与害虫之间的相互作用关系，得出了天敌对害虫的捕食量模型2个。对模型进行主次分析表明，害虫自身密度的大小对天敌的捕食量影响较大。天敌中对捕食量作用最大的是粽管巢蛛，其次是拟水狼蛛，食虫沟瘤蛛的作用稍小。分析天敌间的交互作用表明，天敌个体大、活动能力强、生态位窄及其重叠值高、捕食量大，它们的种内种间干扰程度也大，特别是粽管巢蛛的种内干扰、拟水狼蛛和粽管巢蛛的种间干扰作用十分明显。最后讨论了天敌蜘蛛能有效控制害虫的最大密度，以及在该害虫密度下各种天敌密度的最佳组合。

CONTROL FUNCTION OF THREE SPIDERS FOR BROWN PLANT HOPPER IN COEXISTENT SYSTEM

The foraging behavior of three predators (X1- Oedothorox insecticeps, X2- Pirata subpiraticus, and X3 - Clubiona japonicola) on Brown planthopper (X4 - Nilaparuata lugens) was investigated, as well as how the interference among and within species occurred, by using the rotational composite design of quadratic regression. Two predatory capacity models in the coexistent system of 3 spiders and rice insect pest were obtained. One of them was :Y = 32. 143 1. 625X1 2. 042X2 2. 125X3 11. 125X4-3. 2752X-3. 1502X2-2. 775X32-1. 775X42 0. 438X1X2 0. 188X1X3-0. 063X1X4 -0. 438X2X3 0. 188X2X4-1. 188X3X4The principal efficiency analysis on this model indicated that an increase in rice insect pest density had significantly increased the predation of predators on the insect pest and had a greater effect than any one of predators. Among the 3 species predators, an increase in X3 density had the greatest effect on the increase of predation, X2 had the second and a little greater than X1 the third. As the predator density increased, the inter- and intra - species interference occured, which were related to the size., activity,niche breadth,sniche overlap and searching efficiency of the predators. X3 had the greatest interference between different individuals and with any other predator species, and X2 had the second greatest, which reduced the predation in high predator densities. Because of these, the highest predation was obtained in the prey density of 50 per 4 rice -hills and the optimal proportion of the three predators in the multi -predator prey system was X1:X2:X3 = 6. 9:4. 8:2. 5.