Transformation Of GmWRKY70 Gene Into Soybean By Agrobacterium-Mediated Method

As an important economic crops and oil crops, soybean (Glycine max L.Merr) is a natural resources for vegetable proteins, lipids, minerals, vitamins and so oa It can be available for grain, oil and forage. In recent years, the soybean planting acreage in China has kept decreasing, so the supply and demand balance of domestic soybean must be dependent on the international market to a certain extent, and so our soybean industry is facing a serious crisis. Normally, the growth and yield of soybean are susceptible to the abiotic factors, such as drought, salinity, frost, freezing injury and other environment stresses. The production will sharply declined even total loss under the serious condition.Therefore, many researchers use traditional breeding methods and transgenic technology to increase the yield of soybean by cultivating new varieties. At the same time, the new varieties using the modern molecular biology foster can adapt to different growing conditions, which with better resistant ability can expand soybean acreage while not competing with major grain crops for the land. It is all-important significance for us to improve the soybean production and ensure the national strategy of food security.Five different genotype soybean were analyzed to explore the identification methods of screening salt tolerance soybean. The plant height and aboveground biomass of soybean seedlings after seven days with 0 and 150 mmol/L-NaCl treatment at two-leaves-one-shoot stage respectively can be used to determine salt tolerance soybean selection standard. The plant withering rate after treatment ten days also can be regarded as the selection standard.Genetic transformation of GmWRKY70 gene using Agrobacterium-mediated methods with soybean cotyledonary nodes.With the screening of selectable marker Bar gene and PCR analysis of target GmWRKY70 gene, the results indicated that the target Gm WRKY70 gene have been successfully introduced into the soybean genome.T-DNA integration sites analysis based on reverse PCR was used with the reverse PCR for transgenic soybean strains L-05 and L-08 amplified unknown sequences of flanking sequence of T-DNA integration sites on the soybean chromosomes. Then sequence was analyzed with comparison and T-DNA integration sites was verified using PCR technology. The results indicated that for L-05 strain T-DNA region was forwardly integrated into soybean genome chromosome 10 behind 40,530,783 bp, and for L-08 strain T-DNA region was forwardly integrated into soybean genome chromosome 13 behind 35,524,968 bp.