中文摘要：

在实验室条件下研究了以二种叶螨的不同螨态为猎物对拟长毛钝绥螨后代性比、产卵量及捕食选择性的影响。结果表明：捕食二种叶螨的不同螨态捕食螨的后代都是偏雌的。当供给朱砂叶螨时，捕食全螨态的捕食螨后代雌性比最高，为70．34％，显著高于捕食卵（65．56％）和若螨（63．32％）的，而捕食幼螨的最低，为56．84％；当供给二斑叶螨时，捕食卵和全螨态的捕食螨后代雌性比例分别为68．34％和70．24％，捕食若螨的为64．05％，捕食幼螨的为59．30％，三者间均有显著差异。对同种不同螨态来说，捕食螨最喜食卵，若螨次之，最不喜食幼螨。捕食二种叶螨幼螨的产卵量也最低。试验证实了天敌对猎物的捕食朝着最有利于其生殖的方向这一理论。本文进一步探讨了捕食螨的捕食选择性与后代性比的关系。

英文摘要：

The effect of different developmental stages of two spider mite species on the ottsprlng sex ranos, oviposition and prey preference of the predatory mite Amblyseiuspseudolongispinosus was studied in the laboratory The results showed that the offspring sex ratio in A. pseudolongispinosus was always female-biased regardless of its prey species. With Tetranychus cinnabarinus as prey, female ratio in progeny of A. pseudolongispinosus was the highest （70.34%） when offered all developmental stages of the prey together, 65.56%, 63.32% and 56.84% when offered eggs, nymphs and young larvae, respectively. With T. urticae as prey, female ratioin progeny was 68.34%, 70.24%, 64.05% and 59.03% when offered egg, all developmental stages, nymph and larvae, respectively. Among different developmental stages of both spider mites, the predatory mites preferred for egg, followed by nymph, while larva was the least preferred stage. Fecundity of A. pseudolongispinosus feeding on egg, nymph or all developmental stages was significantly higher than that on larva. The relationship between prey preference and sex ratios of offspring in the predatory mite was discussed.