Study On The Drought Resistance Of Early Rice At The Seedling Stage

Rice is the most important food crop and The drought has become the greatest threat of grain production in China., Accurate and rapid identification of drought resistance of varieties is of great significance for rice breeding and water-saving cultivation. In this experiment,6rice varieties at seedling stage were analyzed on the identification of drought resistance and the physiological basis of drought resistance of different varieties. The results are as follows:1.The height diversification of rice varieties has a close relationship with the drought resistance. Relative rate of the difference height of rice is lower, the drought resistance in rice is higher; on the contrary, relative rate of the difference height of rice is higher, the lower is the drought resistance of rice. Relative rate of the difference height of rice as the index, the degree of drought resistance among varieties for:Ling Liang You211>Xiang Zao Xian24> Zhong Zao39>Zhu Liang You4024> Xiang Zao Xian42>Zhong Jia Zao17;2..Root shoot ratio changes can be used to evaluate the drought resistance of rice, root shoot ratio increased faster with stronger ability of drought resistant. There was a significant difference in the root shoot ratio of seedling before and after the drought treatment,and the root to shoot ratio variation reflects the drought resistant ability of rice;3. There are significant differences between the varieties of leaf area coefficient. The leaf area index for drought resistance indexes,you can sort of drought resistance of each variety. Ling Liang You211>Xiang Zao Xian24> Zhong Zao39>Zhu Liang You4024> Xiang Zao Xian42>Zhong Jia Zao17;4.. Repeated drought in seedling survival rate as the index, it can be sorted on Drought Resistance of each variety:Ling Liang You211>Xiang Zao Xian24> Zhong Zao39>Zhu Liang You4024> Xiang Zao Xian42>Zhong Jia Zao17;5. Under drought stress, the chlorophyll content of different varieties will have varying degrees of rise, each rice varieties SPAD values increased with drought, and the relative conductivity of cultivars with drought stress time prolonged positive growth,but was no significant correlation with drought survival rate; 6.Under drought stress conditions, the content of MDA was negatively correlated with drought resistance varieties; drought resistance the change of proline content was positively related with rice varieties; the in vivo protective enzymes (SOD, POD) activity increased,drought resistance varieties is higher than that of the relatively weak.