白三叶叶片荧光特性对水分胁迫的响应（摘要）（英文）

[目的]从生理角度研究白三叶（Trifolium repens）叶片叶绿素荧光参数对水分胁迫的响应。[方法]以白三叶品种＂海发＂为供试材料,设置75%（无胁迫,CK）、50%（轻度胁迫,LD）和25%（重度胁迫,HD）3个土壤含水量水平对植株进行培养,测定水分胁迫对一系列叶绿素荧光参数的影响,并进行统计学分析。[结果]土壤相对含水量为75%和50%时,白三叶叶片叶绿素荧光参数受到的影响不大,说明白三叶在这2种水分条件下能够正常生长;土壤相对含水量为25%时,初始荧光后极显著高于CK和LD处理,原初光能转化效率（Fv/Fm）、PSⅡ电子传递量子产量（φPSⅡ）和光化学猝灭系数显著降低。[结论]白三叶在重度干旱（HD）条件下,生理机能遭到破坏,不能正常生长,表现出旱害症状。

Response of Chlorophyll Fluorescence Characteristic of Trifolium repens L. to Water Stress

[Objective] The aim was to study response of chlorophyll fluorescence parameters in Trifolium repens L.leaves to water stress from perspective of physiology.[Method] With T.repens cultivar ＂Haifa＂ as tested material,three soil water content levels were set to culture plants,including 75% （no stress,CK）,50% （moderate stress,LD） and 25% （severe stress,HD）,the effects of water stress on chlorophyll fluorescence parameters were determined.[Result] The results showed that the chlorophyll fluorescence parameters changed a little when the relative soil moisture content was 75% and 50%,while the chlorophyll fluorescence parameters such as conversion efficiency of primary light energy （Fv/Fm） of PS Ⅱ,the photochemical quenching coefficient （qP） and the quantum yield of PS Ⅱ electron transport （φPS Ⅱ） decreased respectively when the relative soil moisture content was 25%.[Conclusion] When T.repens in severe drought conditions,the physiological functions were damaged,showing symptoms of drought injury.