转基因烟草的甘露醇合成和耐盐性

土壤的盐碱性是世界许多地区限制植物生长和作物产量的主要制约因素。长期的研究发现:在高盐或干旱环境下,大多数植物在细胞质中开始积累一些低分子量的代谢物,如脯氨酸、甜菜碱、糖醇等。这些物质通过维持高的细胞质渗透压,有利于植物在高盐或干旱条件下的水分吸收。通过基因工程手段,影响或改变植物体内的生理代谢途径,使得植物细胞产生和积累不同的低分子量有机化合物,能够

Mannitol Synthesis and Salt Tolerance of Transgenic Tobacco

With E. colt mtlD gene (encoding mannitol-1-phosphate dehydrogenase) cloned, sequenced and expressed on high level in bacterium, mtlD gene was inserted into a binary vector containing kanamycin resistant gene. Leaf disce of tobacco (Nicotiana to-bacum cv. Huangmiaoyu) were transformed with Agrobac terium tumefaciens LBA 4404 carryimg the chimaeric gene. The resulting Kn-resistant shoots were directly selected and rooted on MS medium lacking growth regulators but containing 1. 0% - 2. 0%NaCl. Twenty transformants were subjected to salt tolerance test in Hcagland's solution adding 1. 75% NaCl. Statistical analysis documented significant differences between transformants and control in mean height and fresh weight at six weeks after the NaCl addition. Gene integration and expression , verified by analysis of PCR-Southern blot and Nothern blot, resulted in mannitol synthesis, on different levels in the detected trans-genie plants.