中文摘要：

对枣园间种牧草对树上天敌功能团的影响及其作用评价进行系统研究。结果表明：两类枣园树上天敌功能团的多样性与优势度系数有明显（P〈0．05）差异，枣园种草对树上天敌功能团的演替产生一定的作用，枣树不同发育阶段中，天敌功能团的群落参数随物候而改变；枣园种草对于受化学农药干扰的天敌功能团种群的恢复与重建有促进作用；根据Sn/Sp、Ei/Pi和ds/dm 3种指数的大小，评价了枣园天敌功能团对害虫的控制作用，发现种草园的天敌功能团对枣树害虫的控制能力要比未种草枣园强；相关性测定表明：天敌群落学的研究中可以用功能团替代物种。

英文摘要：

To understand the influence and action evaluation of the functional groups of natural enemies on jujube trees by intereropped herbage at jujube orchards, a systematic survey was made at Taigu, Shanxi Province. The systematic survey showed that there were significant difference （P 〈 0.05） of the diversity and dominance of functional groups of natural enemies on the trees at the two types of jujube orchards. The result suggested that jujube orchard with herbage have obvious effect to the succession of functional groups of natural enemies on the trees. There were different community parameters of functional groups of natural enemies in the different developing stages of jujube trees. The jujube orchard with herbage could improve the recovering and rebuilding of the population of functional groups of natural enemies which had been severely reduced by spraying of the widespectrum insecticides. So the jujube orchard with herbage is of great benefit to the biological control of pests. The controlling effects of functional groups of natural enemies to pests were estimated according to sizes of ratio of Sn/Sp . Ei/Pi and ds/dm. The results from the sizes of ratio suggested that there were better controlling abilities of functional groups of natural enemies to pests in the jujube orchard with herbage than that without herbage. The result from relativity mensuration showed that the study of natural enemy community was conducted by using functional groups instead of species.