水分胁迫前的干旱锻炼对小麦光合生理特性的影响

为探讨水分胁迫前的干旱锻炼对小麦光合生理特性的影响,采用水培法,对小麦幼苗进行水分预胁迫、解除胁迫和再胁迫处理,研究了水分预处理对干旱条件下小麦生物量、叶绿素及光合作用的影响。结果表明,经过水分胁迫预处理后的小麦在水分胁迫下根系生长明显加快,有利于吸收利用有限的水分,水分利用效率明显高于未经过预处理的小麦,净光合速率、气孔导度、胞间二氧化碳浓度、蒸腾速率和叶绿素含量的下降幅度均低于未经过预处理的小麦,预处理缓解了干旱对小麦光合生理特性的影响。

Effects of Pretreatment of Water Stress on Photosynthetic Characteristics of Wheat Under Water Stress

The aim of this paper is to research the effects of pretreatment on drought resistance of wheat under water stress.Pretreatment,re-watering and water restress on wheat were carried out to study the effects of pretreatment on biomass,chlorophyll,and photosynthesis of wheat under drought stress.The results showed that pretreatment of water stress could make wheat acclimatize itself to the water restress quickly and decrease water stress doing harm to photosynthesis of wheat.The chlorophyll contents of the wheat pretreated by water stress were higher than that not pretreated and the increase of chla/b of the wheat pretreated was less than that not.Pretreatment of water stress could stand against the decreases of photosynthetic rate,stomatal conductance,intercellular CO2 concentration and transpiration rate,and enhance the water use efficiency of the wheat under water restress.The results suggest that pretreatment of water stress can prevent the changes of photosynthetic characteristics of wheat when the same stress recurs.