Studies On Physiological Characters About Drought Resistent Of Maize

This paper studied on physiological and biochemical characters and configuration transformation rule of different resistant maize varieties with different water supply during the whole growth period. The varieties were ZHENGDA 619(drought resistant variety) and JINHAI 5(sensitivity variety). The objective was to discuss the mechanism and some authenticating indexes of maize drought resistant, and then use the conclusions to maize drought resistant breeding. The main results were showed as follows:There were obvious differences between ZHENGDA 619 and JINHAI 5 with different water supply treatments, such as different content of betaine, soluble sugar and praline about maize leaves. The high drought resistant varieties had big changing range with the content of betaine, soluble sugar and praline of maize leaves when the water stress was strong. But the weak drought resistant varieties showed small changing range.There were significant and positive correlations between the activities of POD, CAT and the water stress intensity. But negative correlations between the activities of SOD and the water stress intensity and there were not various differences between the two varieties. The high drought resistant maize varieties answered the high activities earlier and lasted for longer time than low drought resistant maize varieties.The distinctness between different drought resistant maize varieties: ZHENGDA 619 and JINHAI 5 about the changing of the trend of accumulation of Polyamines and water supply was various. The accumulation of SPD, PUT and CAT of high drought resistant varieties increased fast and its high content lasted for longer time at early growth stage. The accumulation of SPM of high drought resistant varieties under strong water stress treatment was much higher than enough water supply treatment. Low drought resistant varieties showed high accumulation of SPD, PUT and CAT at later growth stage. And its accumulation of SPM under strong water stress treatment was little higher than enough water supply treatment.The configuration characters of maize varieties under water stress were different too. High drought resistant varieties grew slowly, but the root system elongated, and the number of roots reduced. These changes were good for maize growing under water stress. And these indexes direct reflect maize growing. So plant high, leaves areas, the number and length of root can all use as the preferred indexes for identifying maize drought resistant.