Screening Of Cold Tolerance Varieties In Rice Germplasm Resources And Cloning Of OsNADPH1 Gene Under Stress Response

A series of physiological and metabolic responses caused by Stress environments such as low temperature, high temperature, drought, high salt, etc, were represented by reversible inhibition on the metabolism and growth, and heavily irreversible damage leading to death. Of all stresses, drought, cold and high salt have the greatest effect on the plant, which are the most contributing environmental factors affecting the plant growth and the crop yield, seriously threatening rice production and output. Therefore, rice resistance research is important and urgent.In this paper more than 900 rice resources were screened of cold tolerance through strict temperature control and partial cold resistant materials were identified, in which one high-performing variety (Lijiang xintuan heigu) was treated with low temperature and drought respectively. A stress response gene OsNADPH1 has been isolated and cloned, and its expression in low temperature and drought has been analyzed. Finally, the possible function of this gene has been discussed. The results are showed as below.1. A large number of test results indicated that there was a certain positive correlation of the cold tolerance between the budburst period and the seedling, tasseling and maturation period. Through the cold tolerance screening during the budburst period, the cold tolerance variety can be approximately predicted at the seedling and flowering periods. 957 local rice resources provided by the National Germplasm Repository were identified for cold tolerance by the temperature gradient screening method. The results showed that 212 first-grade samples were identified by the germination rate, 153 samples with varying degree of green bud rate were identified, 31 samples with stability of both the germination percentage and the green bud rate were identified. 31 seedlings were placed in light and room temperature after being treated with low temperature gradient germinating and all can develop normally with good growth. Under low temperature, lack of green is the first appearance of the non-cold tolerant varieties. The seedlings with lack of green...