转Bt基因棉对棉田寄生物非亲和效应的研究

Non-compatibility Effect of Transgenic Bt Cotton to Parasitoids

采用分期接虫和分期回收的方法,研究常规棉与转基因棉品种棉铃虫寄生性天敌在不同棉花品种间的寄生作用。结果表明:棉铃虫第2～4代发生期以及卵期和幼虫期,转基因棉品种的棉铃虫卵、幼虫寄生率均显著低于常规棉品种。棉铃虫卵期的寄生蜂主要为拟澳洲赤眼蜂(Tricogramma confisum),幼虫寄生蜂为棉铃虫齿唇姬蜂(Compoletischlorideae)等。由此可见转基因棉对棉铃虫寄生性天敌存在非亲和效应。通过对转Bt基因棉国抗22及其亲本泗棉3号棉铃虫不同世代间卵、幼虫寄生率的纵向比较,发现同一品种棉花上不同世代间棉铃虫卵寄生率差异不显著,而幼虫寄生率差异显著。

The results of the relationship between parasitoids of cotton bollworm (Helicaverpa armigera) and trans-genie Bt cottons showed that parasitic rates of egg and larvae of cotton bollworm were notably lower in the transgenic cotton field than in the non-transgenic cotton field. The main egg parasitoid was Tricogramma confisum. The results de-mostrated non-compatibility between parasitoids and transgenic Bt cottons. At the same time, we investigated the population densities of parasitoids on the same cotton during the various generations of cotton bollworm and found that the densities of egg parasitoids was not different significantly between generations of the insect pest and the densities of larvae parasitoids was between various generations of cotton bollworm.