Optimization Of The Transformation System For The Production Of Glyphosate-resistant Soybean

Soybean is the main source of vegetable protein and vegetable oil for humans. Because China has low production capacity of soybean, it is important to develop soybean varieties with improving quality and yield. Herbicide-resistant soybean with great yield potential is the major transgenic crops grown in the world. To develop transgenic soybean for the production, the first priority is to establish an efficient transformation system.In this study, we assessed factors affecting Agrobacterium-mediated transformation system using soybean cotyledonary node, including soybean genotypes, seed germination, the conditions of co-cultivation and other tissue culture conditions. Result showed that YC1 and YC2 are the best cultivars among 19 elite varieties for transformation based on their regenerability and transient expression of report gene. The best seed germination condition is to place soybean seeds on germination medium for one day or soaked in water overnight. In addition, we found 25mg/L lipoic acid could improve transformation efficiency greatly and other factors, such as light, explants orientation, also play important roles in transformation. Results showed that different infection duration from 5min to 120min or different Agrobacterium density have no effect on transient expression and regenerability.Through the research, our soybean transformation efficiency was increased from 0.2% to 3%-4%. The study makes a contribution to basic research of soybean, development of transgenic soybean and development of modern agriculture of China.