Study On The Transformation Of Haploid Populus Simonii×P.nigra With The Salt-tolerant Gene(Bet-A)

The soil salification is a serious problem for the agricultural, forest production and ecological environment. Consequently, study on the mechanisms of salt-tolerance in plants and breeding of salt-tolerant plants has become a key issue in plant biology nowadays. As an important plant osmotic regulators, glycine betaine in plants, under the osmotic stress, can be accumulated in order to give the plants high salt-tolerance by reducing osmotic pressure and maintaining proteinic structure in cell. So genes implicated in expressing glycine betaine are considered as the most important and the most promising plant salt-tolerant genes. Choline dehydrogenase(CDH) isolated from Escherichia coli, can help the expression of glycine betaine efficiently. To get some salt-tolerant plants, the CDH gene , mediated by agrobacterium, was transformed to the haploid of Populus simoniiXP.nigra. In this paper, several factors affecting transformation of the haploid such as pH etc. were studied, and the tissue culture system was optimized. By means of PCR amplification to total DNA extracted from four transgenic plants, it indicated that Bet-A gene had been integrated into the haploid of the hybrid genome.