Comprehensive Analysis Of Drought Resistance From Three New Wheat Cultivars

In order to identify the drought resistance of three new wheat cultivars Xinong 538, Xinong 556 and Xinong 558, three wheat cultivars Jinmai 47, Xiaoyan 22 and Xinong 979 with different drought resistance and large area promotion were taken as controls,The physiological indexes and agronomic character indices of the different wheat cultivars in germinating, seedling and later development stages, are investigated respectively by means of drought stimulation indoor and field natural drought stress. The comprehensive evaluation for wheat drought resistance was conducted with correlation analysis, principal component analysis and subordinate function analysis. The results indicated that:1. With the different concentrations of PEG-6000 treatment, germination potential, germination rate, chlorophyll content and relative water content decreased, while antioxidative enzyme activities(SOD, POD, CAT), MDA content, proline content and relative conductivity increased at different levels. The trend of coleoptile length and soluble protein content were different among the varieties. The 12 indices was transformed to three(15% and 20% PEG-6000) or four(5% and 10% PEG-6000) independent and synthesized indices by principal component analysis, and the accumulative contribution rate of them were achieved 92.61%%, 92.96%, 88.74% and 93.12%. In case of the synthetic evaluation value(D), the six wheat cultivars were divided into three groups, “Xinong 538” and “Jinmai 47”, “Xiaoyan 22” belonged to the high drought resistance group. “Xinong 558” belonged to the medium drought resistance group. “Xinong 556” and “Xinong 979” belonged to the low drought resistance group.2. In field under natural drought conditions, there existed different degrees of correlation between different indices, and each index had different effects on the drought resistance of the varieties. Through principal component analysis, the 9 physiological indexes and plant height were transformed to three independent and synthesized indices(heading stage, filling stage and grain jointing stage), the 9 agronomic characters indexes were transformed to two independent and synthesized indices(mature stage.), and the accumulative contribution rate of them were achieved 93.67%、87.16%、92.29% and 89.56%. In case of the synthetic evaluation value(D), the six wheat cultivars were divided into three groups, “Xinong 538” and “Jinmai 47” belonged to the high drought resistance group. “Xinong 558” and “Xiaoyan 22” belonged to the medium drought resistance group. “Xinong 556” and “Xinong 979” belonged to the low drought resistance group.3. The results was identified comprehensively from drought stimulation indoor and natural drought stress. Xinong 538 is the highest among the synthetic evaluation value. With clustering analyses, “Xinong 538” and “Jinmai 47” belonged to the high drought resistance group. This performance is consistent with its production on, together with its outstanding comprehensive agronomic traits. Therefore, Xinong 538 can be used as wheat drought resistance breeding parent materials...