不同抗旱类型小麦品种开花期光合速率与抗旱性的比较研究

对田间不同水分条件种植下的不同抗旱类型小麦品种开花期旗叶的光合速率与抗旱性的关系进行了比较研究，结果表明，供试品种在正常水分处理条件下，开花期兴合速率（Pn)无明显判别，而在旱处理条件下，开花期光合速率差别很大，幅度在7－23umol.m^-2.s^-1。抗旱性较强的品种晋麦33，河农859在开花期保持较强的光合速率，有利于其适应旱胁迫；冀麦3235，中麦9号开花期兴合速率受到很大抑制，可能是使其抗旱系数（DRC）和抗旱指数（DRI）较小并使其抗旱性较差的因素之一，昌乐5号，温麦6号虽然在开花期强的光合速率，但其DRC和DRI都很低， 简明开花期的光合速率对其影响并不大，其抗旱性差可能是开花期后生理代谢过程受到影响的结果，不同的小麦种质资源在不同的生育阶段不同的抗旱机制。

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.