Co-overexpressing AhBADH And PsCAT Genes Can Enhance The Adverse Resistance Of Transgenic Tobacco And Poplar Plants

The plant growth is affected by many factors, especially drought and salt, which are usually companied by the strong sunshine. In addition, drought and salt with the strong sunshine will hurt regulating ability of osmotic pressure and oxidation-resistance ability of the plant and in turn destroy the organization and function of chloroplast, reducing photosynthesis of plant greatly. If we use the transformation of AhBADH into plant and overexpressing in the plant , utilizing the function of oxidation-resistance,osmosis regulation and protein protection, we can enhance plant drought-resistance ability, regulating ability of osmotic pressure and oxidation-resistance ability .Therefore, in this study, AhBADH and PsCAT genes were constructed in same expression vector and transferred into tobacco and poplar, respectively, to enhance the plant adverse resistance.The main result includes:1. We Constructed the fusion gene of PsCAT and Tr (rbcS-3'gene) and AhBADH into a same expression vector with independent ORFs, then transfered the fusion gene into tobacco and poplar mediat by Agrobacterium tumefaciems, respectively. More than 30 plants were selected to survive on the culture medium with antibiotics, which includes tobacco and poplar plants with single AhBADH gene, with PsCAT gene or with both these two genes. The molecular biological tests and plant physiological analysis were carried out to verify these transgenic plants.2. Object genes had been integrated into plant genome and could express regularly, which verified by PCR, Northern Blot and Western Blot. The expressed enzyme could be transferred into chloroplast directively with the help of rbcS-3 transferring protein.3. Under 20% PEG6000, the damnification of plasmalemma, degradation degree of chloroplast and damnification degree of PSâ…¡in the transgenic tobacco and poplar (including tobacco and poplar plants with single AhBADH gene, with PsCAT gene or with both these two genes) are all lower than those in wild type tobacco and poplar, which indicated that AhBADH and PsCAT gene actually enhanced the plant adversity-resistance ability. In addition, the adversity-resistance ability of the plants with both AhBADH and PsCAT gene are higher than that of the plants with only one gene.4. Treated with paraquat, the oxidation-resistance ability of three kinds of transgenic plants are higher than that of wild plants. And the resistance of the plants with both AhBADH and PsCAT gene are higher than that of the plants with only one gene.5. Treated with 200 mM NaCl, the salt-resistance ability of three kinds of transgenic plants are higher than that of wild type plants. And the resistance of the plants with both AhBADH and PsCAT gene are higher than the plants with only one gene. In conclusion, transgenic plants with AhBADH and PsCAT gene enhanced the regulating ability of osmotic pressure and oxidation-resistance ability, in turn enhanced the ability to resist aridity, salt, high and low temperature. And co-overexpressing AhBADH and PsCAT gene can enhance the adverse resistance ability more efficiently.