Transformation Of Populus With AtNHX1 Gene And Verification Of Its Salt Tolerance

In this study, stem of populus×euramericana cv.'74/75' was used as experimentmaterial. During the establishment of high frequency regeneration system, Na⁺/H⁺antiporter gene of Arabidopsis thaliana (AtNHX1) was transferred into populus byAgrobacterium tumefaciens transferring system. Thus, a subculture system and a highfrequency regeneration system were established and 126 AtNHX1 transgenic plants wereobtained, verified by PCR test, sequencing of PCR product and Southern blot analysis ofgenomic DNA of populus as well as preliminary verification of its salt tolerance. The mainresults of the experiment were described as follows:The rate of regeneration buds was100% in the induction medium containing MS+0.5mg/L 6-BA+0.1 mg/L NAA. It is the basis of Agrobacterium tumefaciens transferringsystem.Diluting Agrobacterium with MS was the best medium; the concerntration was OD₆₀₀=0.5., and the suitable infection duration was around 10～15 min. The appropriatefor-culture and co-culture duration was 2d respective and the optimum concentrations ofkanamycin and Carb for transformed stem of populous×euramericana cv. '74/75' were 70mg·L^-1 and 500 mg·L^-1, respective.337 Kan resistant plants with AtNHX1 gene regeneration plants were obtained andPCR analysis showed there were 126 positive plants with AtNHX1 gene. The result ofSouthern analysis demonstrated that AtNHX1 gene was introduced into genome ofPopulus×euramericana cv. '74/75'.The test of salt stress had been done to the positive plants transformed AtNHX1 geneof populus. It is demonstrated that the transgenic plant showed stronger salt-resistant thanthe control plant.