转Bt基因棉田朱砂叶螨及其天敌生态位研究

研究了转Bt基因棉田与常规棉田朱砂叶螨及其主要捕食性天敌的时间与空间生态位.结果表明,转Bt基因棉田朱砂叶螨的时间与空间生态位、天敌的空间生态位以及龟纹瓢虫、异色瓢虫、塔六点蓟马、食卵赤螨和其他天敌的时间生态位宽度大于常规棉田,朱砂叶螨与天敌的时间与空间生态位重叠指数也大于常规棉田.运用生态位的观念阐述了转Bt基因棉与害虫之间的关系,指出朱砂叶螨仍是长江中游棉区的主要害虫.

The Niche of Tetranychus cinnabarinus and Its Predatory Enemies in the Bt Cotton Field

The temporal and spatial niche of Tetranychus cinnabarinus and its predatory enemies in transgenic Bt cotton and conventional cotton field in Mid-Changjiang River valley has been studied.The results suggested that there were no significant differences in population density of Tetranychus cinnabarinus between two types of cotton fields,whereas Tetranychus cinnabarinus in Bt cotton field had wider breadth of temporal and spatial niche than that in conventional field.This implied that there were a longer period of occurrence and more complex damage about Tetranychus cinnabarinus to Bt cotton than to Non-Bt cotton.At the same time,investigation also displayed that all of nature enemies had wider spatial niche breadth,Propylaea japonica,Harmonia axyridis,Scolothrips takahashi and Abrolophus sp.had wider temporal niche breadth,and Tetranychus cinnabarinus possessed higher overlap in temporal and spatial niche with its predators in Bt cotton.This indicated that competition between predators became more severity,which would strengthen control to Tetranychus cinnabarinus in Bt cotton field.The reason was analyzed by the theory of niches.