Effect Of Transgenic Dreb Soybean Dongnong50on Soil Microbes

In recent years,the yield of the soybean is reducing ever year.And the drought is the major bottleneck in soybean production. With the development of the transgenic technology, planting the transgenic drought-resistant-gene soybean will be an important way to solve this problem. Dehydration responsive element binding (DREB) is a kind of transcription factor that regulates stress tolerance-related genes.Transgenic DREB soybean can improve the ability to drought and increase the production.But with the continuous expansion of cultivated area of the transgenic plants, the risks posed by transgenic plants on the ecological environment and the security issues are paid close attention.We should assess the safety of planting transgenic plants. Microbe is an important component of soil.The changes of the amount and the diversity of the microbe can represent the changes of soil ecological environment. And it also is an important link of transgenic plants safety assessment.This study chose the transgenic DREB soybean Dongnong50and soybean Dongnong50under normal water condition and drought stress condition as research materials, and chose pot culture method to study the change of the amount of microbe, soil biochemical function intensity and the community diversity. This study will provide a reference for the safety evaluation of transgenic soybeans commercial production. Main contents and results of this study are as follows:1. The amount of the bacteria, fungi and actinomycetes were not affected by transgenic DREB soybean under normal water condition and drought stress condition from the seeding stage to podding and seed filling period.Transgenic soybean under normal water condition had no significant effect on the amount of nitrogen transforming bacteria from the seeding stage to harvest time. Transgenic soybean under drought stress condition promoted the growing of the nitrogen-fixing bacteria in the flowering stage,and had no significant impact on the number of nitrogen-fixing bacteria in other stages. Transgenic soybean under drought stress condition decreased the number of the ammonifying bacteria and denitrifying bacteria in the flowering stage and podding and seed filling period. Transgenic soybean under drought stress condition had no notable effect on the number the ammonifying bacteria and denitrifying bacteria in other stages.In the whole growth period, the number of the nitrifying bacteria was not affected by the transgenic soybean under drought stress condition.2. Transgenic DREB soybean under normal water condition had no significant effect on soil biochemical function intensity from the seeding stage to harvest time. Transgenic soybean under drought stress condition promoted the intensity of nitrogen fixation in the flowering stage,and had no significant impact on it in other stages. Transgenic soybean under drought stress condition restrained the ammoniation intensity and denitrification intensity in the flowering stage and podding and seed filling period, and had no significant impact on the ammoniation intensity and denitrification intensity in other stages. In the whole growth period, the intensity of nitrification intensity was not affected by the transgenic soybean under drought stress condition.3. Transgenic DREB soybean under normal water condition had no notable effect on the activity of the hydrogenenzyme, urease, phosphatase, cellulose enzyme from the seeding stage to podding and seed filling period.Transgenic soybean under drought stress condition strengthens the urease activity in the flowering stage,and had no notable effect on it in the seeding stage and podding and seed filling period. Transgenic soybean under drought stressed condition inhibits the activity of the sphatase and cellulose enzyme from the seeding stage to podding and seed filling period, and had no notable effect on hydrogenenzyme.4. Transgenic DREB soybean under normal water condition and drought stress condition had no significant effect on the diversity of the bacteria, fungi and actinomycetesl from the seeding stage to podding and seed filling period.Transgenic DREB soybean under normal water condition reduced the diversity of the nitrogen-fixing bacteria in the seeding stage and flowering stage,and had no notable effect on it in other stages. Transgenic soybean under drought stress condition reduced the diversity of the nitrogen-fixing bacteria in the flowering stage,and had no notable effect on it in other stages.Among sequences g7,g13,g15,g19were of Alphaproteoba-cteria.Others were of Betaproteobacteria.Among the sequences of Betaproteobacteria, g12was of Azonexus,and others were of Burkholderia.Transgenic soybean under normal water condition and drought stress condition improve the diversity of the ammonia-oxidizing bacteria in the harvest time.The diversity was not affected in other stages. All the sequences were of Nitrosovibrio and Nitrosospira in Betaproteobacteria.Transgenic soybean under normal water condition had effect on the community structure of denitrifying bacteria and improve the diversity in the harvest time.In others stages the denitrifying bacteria was not affected by the transgenic soybean under normal water condition. Transgenic soybean under drought stress condition had no notable effect on the diversity of denitrifying bacteria in the whole period. Among the sequences,f6and f10were of Betaproteobacteria,and f6wae Cupriavidus, f10was of unclassified Rhodocyclales.Others were uncultured.