Abstract: With the popularization and application of transgenic Bt crops,and increasing attention has been paid to their potential impact on ecological environment and other aspects.And,as the development of detecting techniques for Bt toxin protein and soil were made by oversea researchers.This paper reviewed the current situation of the studies on the insecticidal characteristics and detecting methods of toxin proteins released by transgenic Bt crops,the potentical risk of their field release,the impact of soil mineral,organic matter and organo mineral complex on the persistence of purified Bt toxins,and the behavior of Bt toxins in rhizospheric soil.Based on our researches,several problems which should be paid attention to in related studies were also pointed out.

Key words: light condition, population characte-ristics, temporal and spatial variation, Fargesia decurvata, canopy structure