Comparative studies on photosynthetic rate and drought resistance at flowering stage of winter wheat varieties with different drought resistant ability

wheat varieties with different drought resistant abilities were planted in normal irrigation or drought conditions. The photosynthetic rate (Pn) of flag leaves at flowering stage and their drought resistant abilities were compared. The results showed that the tested wheat varieties had little different Pn rates at flowering stage at normal irrigation condition. Under drought condition, the Pn rates were significantly different among the tested varieties at flowering stage: Jinmai 33, Henong 859 had higher Pn rates at flowering stage, which was useful to their drought resistance, their DRC and DRI were the highest. The Pn rates of Jimai 3235 and Zhongmai 9 were greatly influenced by drought at flowering stage, this may be one reason for influencing their DRC and DRI. Changle 5, Wenmai 6 had higher Pn rates at flowering stage, However, their drought resistance was poor, their DRC and DRI were the lowest. It indicated that the poor drought resistance of Changle 5, Wenmai 6 were controlled by other physiological metabolism. The drought resistant mechanisms were different among different wheat varieties.