Improved Transgenic Technology To Soybean (Glycine Max) Cotyledonary Node

Plant genetic engineering techniques have unprecedented potential for crop improvement. The technique of genetic transformation has been applied in the improvement of seed quality and disease resistance in soybean. Based on the principle and advatages of transgenetic technology the agrobacterium-mediated technique was eventually chosed as the basic transformation method. Sterile seedling, explant choice, agrobacterium infection and coincubation, and concentration of plant hormone during the training period were tried in the investigation of plant regeneration, in order to optimize the medium for regeneration and greatly improve the transgenic efficiency.The agrobacterium-mediated transgenic technique combined with the treatment of boric acid was studied for the transformation of foreign gene Bt to explant, soybean cotyledon nodes. 11 different boric acid concentration processing multiple shoot of soybean cotyledons section were chosen, then transfomed soybeans during the induction period were treated seperately by the concentration of typical boric acid. The results showed that the transformation seedlings without boric acid had no growing point, and the roots growth were also severely restrained.At the same time,the high boric acid concentration growed more callus, the explants short-term easily died, which were not conducive to the regeneration of transformed multiple shoots. However,the shoots regenerated from the explants were multiplied best at appropriate boric acid concentration, and the transformation ratio reached 3.3%. Regenerated seedling were screened by genomic PCR amplification and resistant seedlings on inductive medium was obtained and proved to be positive by reverse PCR and Southern blotting. It was demonstrated that the target gene had been transformed into the soybean genome.