Primarily Studies On The Genetic Transformation Of AtNCED₃ Gene And Its Drought And Salt Tolerance In Rice

In our country the salt disperative soil is about 1/5 of arable land and it will be expanded in the future .The rice production loss caused by soil drought and salinization is too large to be estimation. In order to enhance rice tolerance to drought and salt stress, we transformed AtNCED₃ gene into rice by Agrobacterium tumefaciens.We constructed RD29A:: AtNCED₃ Agrobacterium expression vector. Then transformed it into zhong hua 10 calli using 50mg/l hygromycin as selection. At last regenerated rice plants were got. Transgenic rice plants were analyzed by PCR , results showed that the AtNCED₃ gene had been integrated into rice genome.By hygromycin-resistant experiment we found most of transgenic plants of generation TO segregated followed Mendal' inheritance law 3:1, however.the wild-type plants all died.Average transpiration rate of transgenic plants was decreased by 28.2% compared to wild-type plants under normal growth conditions ,which showed transgenic plants relieved water-fleeting by decreasing transpiration rate. At the meanwhile, transgenic plants of generation TO and T1 were analysized drought and salt tolerance respectively .Results showed that different transgenic lines could grow normally in 100mM NaCl or 200mM monital MS medium,but the growth of wild-type plants were inhibated deeply .Successively , transgenic plants had higher ABA content than wild-type plants in different stress . The results prove that the expression of AtNCED₃ reinforced drought and salt tolerance of rice.