| Transgenic crops are grown on an increasingly large scale throughout the world, and their increased use has been accompanied by public concern about their potential ecological and environmental impacts. The persistence and interaction of proteins derived from transgenic crops in soil and their effects on soil microbial are essential information when investigating their effects within the soil ecosystem. The functional diversity of microbial communities in the rhizosphere of transgenic soybean PAT and its parental isoline PAT1, transgenic soybean ALS and its parental isoline ALS1, and local major soybean zhonghuang13 was analyzed under field experiment by Biolog-ECO technique. Soil samples at the depth of 0~20 cm were collected in September 2011 at mature stage. The functional diversity of the soil microbial communities from the different samples was further analyzed by different techniques, such as statistical analysis and diversity index evaluation of the soil microbia. The results showed that the average well color development（AWCD） which directly reflected the microbial activities of changed in the following variation：All the treatments exhibited the elevation of AWCD during the first 48 hours of incubation, but the differences among the treatments were obvious. Both transgenic soybean PAT and ALS caused high increase of the AWCD while the corresponding non-transgenic parental isoline and local major soybean zhonghuang13 had less affection on the AWCD. During the whole incubation process, the soil microbial activity of transgenic soybean PAT and ALS was higher than the corresponding non-transgenic parental isoline, and the local major soybean zhonghuang 13 was between the transgenic soybeans and non-transgenic parental isolines. The species evenness（J）and dominance index（D） of the soil microbial communities of transgenic soybeans showed no significant difference（P>0.05） compared with the non-transgenic parental isolines, The Shannon-Wiener index（H） of the soil microbial communities of the transgenic soybean ALS was higher than the its parental isoline ALS1, with no difference between the transgenic soybean PAT and its parental isoline PAT1. The principal component analysis（PCA） indicated that the variance contribution rate of PC1 and PC2 were 37.28% and 17.19%, respectively. The correlation coefficients between main substrates and PC1 or PC2 indicated that the main carbon sources for soil microbes were carbohydrates, amino acids, carboxylic acids and polymers in all treatments. The carbon source utilization mode and metabolic function of the microbial communities were similar among the transgenic soybean PAT, the parental isoline PAT1, the parental isoline ALS1 and local major soybean zhonghuang13, unless the transgenic soybean ALS． |
