转基因杨棉复合系统对节肢动物群落结构的影响

Effects of Transgenic Poplar-Cotton Compound Ecosystem on the Structure of Arthropod Community

通过对转基因杨+转基因棉、转基因杨+非转基因棉、非转基因杨+转基因棉、非转基因杨+非转基因棉4种杨棉复合系统节肢动物群落进行调查,运用群落生态学原理和方法分析了转基因杨棉复合系统对节肢动物群落结构的影响。研究表明,与其他3种复合系统相比,转基因杨棉复合系统对节肢动物的群落结构产生显著影响,对靶标类害虫有极强的抑制作用,有助于控制靶标类害虫的发生,但是会造成其他非靶标害虫种类和数量增加,并有上升为主要害虫的趋势,并引致天敌的增殖。从抗靶标类害虫效果看,转基因杨棉复合系统是值得推广的农林种植模式,且Bt转基因棉田益害比为0.5622。但综合分析常规杨棉复合系统与转基因杨棉复合系统群落结构特征指数,转基因杨树林中优势类群单一,而在非转基因杨树林中优势类群则较复杂,转基因杨棉复合系统使均匀度和生物多样性降低,可能会影响正常的生态营养循环流动系统,因此在Bt转基因杨棉复合系统需导入生态调控策略。

The present research were designed to reveal arthropod community of 4 different poplar-cot- tons compound ecosystem ： Bt poplar ＋ Bt cotton patterns, Bt poplar ＋ non Bt eotton patterns, non Bt poplar ＋Bt cotton patterns and non Bt patterns＋non Bt cotton patterns,and to analyze the influence of Bt poplar cotton compound ecosystem on the community structure by using community eeologieal principals and method. The results indicated that the transgenic Bt poplar and transgenie Bt cotton agro-forestry eeosys- tern had dramatic effect on the community structure of arthropod by comparison with other 3 compound e- cosystems had significant impact on controlling the numbers and species of target insects and helped to control occurence of target insects,but to cause the increase of the numbers and species of other nontarget insects. Meanwhiles the Bt polar-Bt cotton compound system can increase the numbers and species of non- target inscets,and become a dominance population with natural pests. From the view of bollworm-resist- ant,it is worth spreading the agro-forestry arrangement patterns, because the average ratio between good and harm of Bt transgenic cotton of Bt transgenic cotton was 0. 5622. While,analyzing the diversity index, richness index, evenness index of Bt polar- Bt cotton ecosystem community structure, which revealed that thestability of community was decreasing, its dominant populations became singleness, maybe disturb the eco- nutrition recycle. Accordingly, in order to keep the stability of the compound ecosystem, the transgenic agroforestrial ecosystem,the strategy of ecological management should be introduced.