转Bt-cry1Ac基因棉花叶片中杀虫蛋白在环境中的降解动态

 采用ELISA方法研究了Bt棉花叶片中Cry1Ac杀虫蛋白在不同环境条件空气介质中和土壤介质中的降解规律。结果表明，不同环境下Bt杀虫蛋白降解趋势有明显差异。不同温湿度及光照条件的空气介质中，Bt杀虫蛋白的降解速度一般在初期较快，经过短暂的缓慢降解阶段后进入相对稳定状态（含量50 ng·g-1左右）。高温低湿条件下，Bt杀虫蛋白降解较快，达到稳定水平的时间短。Bt杀虫蛋白在光照和非光照环境下的的降解动态没有显著性差异。自然条件下Cry1Ac蛋白在土壤介质中初始阶段降解迅速，30 d后降解了85%左右。随着冬季的到来, 杀虫蛋白降解趋于缓慢。次年春天后，杀虫蛋白的降解加快，至 4月下旬检测不到Bt杀虫蛋白。

Degradation Dynamics of Cry1Ac Insecticidal Protein in Leaves of Bt Cotton under Different Environments

The degradation dynamics of Cry1Ac insecticidal protein in the leaves of Bt cotton while exposure to air and soil mediums under different conditions were investigated in both the laboratory and in the field. The results showed that the degradation trends under different situations were different. Bt insecticidal protein in cotton leaves degraded rapidly in first several days, then got slowly and entered a relative stable stage in which Cry1Ac protein content kept at a concentration about 50 ng·g-1. The higher temperature and lower humidity significantly increased degradation speed of the toxin, which shortened the period for the content of the protein to get into stable stage. However, there were no significant difference of the degradation under light or dark treatments. In natural environment, the insecticidal protein in Bt cotton degraded much rapidly in the initial period, it reached 85% in first month, and slowered during winter season, then degraded quickly in next spring until to be undetectable in late April.