| Based on the interaction system of wheat(maize) -cotton system ,natural enemies and insect pests ,the structure and function of arthropod community was studied. The law of natural enemies and insect pests community reestablishment construct was probed. The spatial pattern of natural enemies and insect pests and the spatial relation between natural enemies and insect pests were analyzed. The effects of different agricultural measures on the community were compared. And the mechanism of controlling the function of natural enemies to insect pests in wheat(maize)-cotton system in Huimin City of ShanDong province, is revealed in this paper ,by using the field test ,indoor trial, outdoor experiment and field investigation, and the knowledge and technique of biology, ecology, taxonomy, geo-statistics, systematic and computer etc. The results are summarized blow.1 The relation of structure and dynamic among species pool, exchange pool and subject community in cpmmunity reestablishment was probed by the theory of island biogeography and reservoir sources hypothesis of community reestablishment. Species pool was the latent settler in all, which can enter the living grounds before the subject community reestablished . Exchange pool was the living being community, which can enter it after the subject community reestablished. Exchange pool can supply the settler for the reestablishment community and sanctuary for the outgoing settler community.2 The structure and dynamics of the arthropod community and groups in whcat(maize)-cotton system were studied at different agricultural measures by using richness, mean density, diversity and evenness indices. The result proved that the effects of different farming system, cultivated forms and pests control methods were remarkable. Al 1 the indices of them in different sample field fluctuated with different levels, they were at peak in middle cotton growing stage on the whole and the diversity and evenness indices fluctuated more. The community indices were significantly different among natural enemies and insect pests at different agricultural measures. The effect of pest control method was the largest that of farming system the second and the cultivated forms the lowest. And the effect differences of them were the largest to the insect pests , and the lowest to the natural enemies.3 The result of the releasing experiment of Trichogramma confusum showed the eggparasite rates in the second and the third forth generation were respectively .68.35% and 78.67%. The egg parasite rates in chemical control fields were respectively 9.54% and 6.34%. Compared with chemical cotton fields, Insecticides application of IPM cotton fields decreased by 60-80%,the damages of cotton boll declined by 41.7%,the control expense was saved 11.5-15.0% yuan per acre.4 The using of bio-information and bio-pesticide to control and manage insect pests community.Based on understanding of the dynamic of the main pests and dominant natural enemies, The strategies of the preservation, utilization and regulation of nat ural enemies guild were proposed.
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