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【目的】探究海拔因素对烟田昆虫群落结构及多样性的影响,分析不同海拔烟田害虫发生情况和天敌昆虫对害虫的控制情况,为烟田病虫害防治提供依据。【方法】在陕西陇县选择不同海拔烟田,采用棋盘式取样法抽取样株并记录烟株上各种昆虫的种类和数量,研究不同海拔烟田昆虫的时序动态、群落组织水平及相似性。【结果】烟田昆虫群落包括9目25科32种,其中害虫7目18科21种,天敌昆虫5目8科11种,主要害虫有烟蚜和斑须蝽,主要天敌昆虫有烟蚜茧蜂、丽草蛉、黑带食蚜蝇和七星瓢虫。高海拔烟田昆虫群落种类较丰富,群落结构较稳定,抵御环境变化与自我调节能力较强,多样性指数最高。中海拔和高海拔烟田昆虫群落相似性系数最高,各海拔烟田昆虫群落差异较大。8月中旬为各烟田害虫发生高峰期。烟蚜在田间出现时间较斑须蝽早,消失晚,田间数量较斑须蝽大。低海拔烟田烟蚜和斑须蝽数量较高海拔和中海拔烟田高。【结论】海拔高度差异及其所导致的物候差异是影响烟田昆虫群落结构的重要因子。
【Objective】 The objective of this study was to investigate the effects of elevation on the structure and diversity of insect communities in tobacco fields and to analyze the occurrence of insect pests at different altitudes and control of pests by natural enemy insects to provide the basis for the prevention and control of pests and diseases in tobacco fields. 【Method】 Species and quantity of various insects on tobacco plants were sampled by checkerboard sampling at different altitudes in Longxian, Shaanxi Province. The temporal dynamics, community organization and similarity of insects at different altitudes were studied . 【Result】 The results showed that the tobacco insect community consisted of 9 species, 25 families, 32 species, of which 21 species were 18 orders and 21 families, while the natural enemies were 5 orders, 8 families and 11 species. The major pests were Myzus persicae and Akebia stink bug, Bee, prickly heat, black-eyed hoverfly and Coccinella septempunctata. Insect communities in high altitude tobacco fields are rich in species, stable in community structure, strong in resistance to environmental changes and self-regulation, with the highest diversity index. The similarity coefficient of insect communities in mid-altitude and high-altitude tobacco fields was the highest, and the insect community varied significantly in all altitudes. In mid-August for the pest crop fields peak. Myzus persicae appeared in the field earlier than the spotted stink bug, disappear late, the number of fields larger than spotted stink bug. Low altitude tobacco aphids and spotted stink bug higher number of high altitude and mid-altitude tobacco fields. 【Conclusion】 The differences in altitude and the phenological differences caused by them are important factors affecting the insect community structure in tobacco fields.