盐碱旱地转Bt基因抗虫棉田主要害虫及其天敌种群消长动态

【目的】近年来,我国长江流域和黄河流域棉花面积锐减,种植区域向滨海盐碱地或干旱地转移。研究盐碱旱地转基因棉田与非转基因棉田昆虫群落差异,可为盐碱旱地对转基因棉田生物影响和盐碱旱地转基因棉田害虫防治提供理论指导。【方法】在山东东营和河北枣强盐碱干旱地转Bt基因棉田分别设置常规施药田和非施药田,进行了系统的田间昆虫种群消长动态的调查和统计分析。【结果】中轻度盐碱旱地种植转基因棉花对靶标害虫棉铃虫具有较好的控制作用;与非转基因棉花相比,对其他非靶标害虫棉蚜、烟粉虱和盲蝽及自然天敌龟纹瓢虫、草间小黑蛛种群数量无显著影响,草蛉种群数量在转基因棉田低于非转基因棉田;喷施化学农药对棉铃虫幼虫和棉蚜的防治作用较好,对烟粉虱和盲蝽的防治效果年度间和试验点间有差异,对龟纹瓢虫的杀伤力较大,对草间小黑蛛和草蛉未见明显影响。【结论】盐碱旱地对棉田不同的害虫和天敌影响不同,且转基因棉田与非转基因棉田昆虫群落结构与对照棉田无显著差异。

Population dynamics of the main pests and their natural enemies of Bt transgenic cotton field in saline alkali and drought land

Aim] The Yangtze River Basin and the Yellow River Basin have decreased sharply leading to cultivation of cotton on coastal saline or dry lands. The objective of this research was to compare the impacts of transgenic versus non-transgenic cotton cultivation on pest insect populations and the efficiency of pesticides for pest control.Method] The paper surveyed and analyzed the insect population dynamics in transgenic cotton fields in Dongying in Shandong Province, and Zaoqiang in Hebei Province, which were sprayed or not with pesticides in 2013 and 2014.Result] The transgenic cotton in saline alkaline and dry soil had better control effect on target pests than non-transgenic cotton. The populations of non-target pests such as Aphis gossypii, Bemisia tabaci and Miridae, and predators, such as Propylaea japonica and Erigonidium graminicolum, were not significantly different between the two types of cotton fields. The Chrysopa population was smaller in transgenic cotton fields than non-transgenic cotton fields. Chemical pesticides effectively controlled Helicoverpa armigera eggs, larvae of cotton bollworm and cotton aphids. The control of Bemisia tabaci and fleahopper differed among fields and yearly, with greater effects observed for Propylaea japonica.Conclusion] The effects of saline alkali drought land on different pests and natural enemies in cotton fields were different, and compared with the non-Bt cotton, the insect community structure of transgenic cotton fields in saline and dry land showed no difference.