The Study On Physiological Function Of Cold Tolerence By Transfering ICE1 Gene Into Rice

Heilongjiang is located in the alpine region. Chilling injury is one of the main environmental factors to limit the high and stable yield in Heilongjiang rice. Research to improve cold tolerance in rice has important theoretical and practical significance. Overexpression of gene ICE1 can improve the cold tolerance in rice.In this research, the positive T4 generation of transferring ICE1 rice and the rice (Oryza sativa L.cv Kenjiandao No.10) were used as the materials. We used molecular biology methods to test the hereditable character of exogenous gene ICE1 in transgenic rice; In addition researched the influence of low temperature conditions on the activity of membrane system(conductivity and MDA) and antioxidant system (SOD, CAT, POD) and changes over nutrient(N, P, K)under natural condition and low temperature stress of T4 generation transgenic ICE1 rice through the physiological and biochemical experiments. And instructions the reasons of improve the cold resistance of transgenic plants. The experiment results of the study on the cold tolerance of T4 transgenic rice show as follows:1. This research used PCR and hygromycin screening methods to test the 3 lines of T4 transgenic rice, a total of 172 plants. The test results showed that using the method of PCR to test ICE1 gene and using the tissue culture to test the HPT gene have a same result. And exogenous ICE1 gene has been stably inherited in transgenic rice.2. Transgenic rice showed significant cold tolerance at low temperature for 10 days.3. Under low temperature stress, the non-transgenic rice conductivity and MDA content significantly increased with the stress time increased. However conductivity and MDA content of transgenic rice was significantly lower than non-transgenic rice. Instructions transgenic ICE1 rice put off period of membrane damage under low temperature stress.4. SOD and CAT in transgenic rice has been maintained at a high level, and POD in transgenic rice has been maintained at a low level at before and after treatment under low temperature stress. Instructions the mainly enzymes which eliminating the free radical were SOD and CAT in transgenic rice under low temperature stress.5. Nitrogen and phosphorus of transgenic rice shoots content was lower. With the extension of low temperature stress, nitrogen and phosphorus of transgenic plants content increased, nitrogen and phosphorus of non-transgenic plant decreased. Potassium of Transgenic compared and non-transgenic plants content at the same levels in the initial time, but it has been maintained at a high level under the low temperature stress. Nitrogen content of transgenic rice seedling root has been maintained at a lower level, but phosphorus and Potassium has been maintained at a higher level before and after low temperature stress. It showed that the transgenic rice seedlings adjust content of nitrogen, phosphorus and Potassium K to improve cold tolerance.6. In the normal condition, nitrogen and phosphorus contents in mature the transgenic ICE1 rice and non-transgenic rice was no significant difference. But potassium in transgenic rice shoots increased, underground parts reduced.