【摘要】 在人工气候室水培条件下,选用3个不同抗旱类型的冬小麦品种,研究了水分胁迫对冬小麦幼苗叶绿素荧光参数的影响.结果表明:水分胁迫下,冬小麦幼苗可变荧光 Fv 、最大荧光 Fm 、可变荧光与最大荧光比 Fv/Fm 、可变荧光与初始荧光比 Fv/Fo 、光化学淬灭系数 qP 均降低;而初始荧光 Fo 与非光化学淬灭系数 qNP 则升高,说明光系统 PS 受到了伤害,使得PS 原初光能转换效率 Fv/Fm 、PS 潜在活性 Fv/Fo 降低;光合电子传递、光合原初反应过程受到抑制,起光保护作用的热耗散提高.但水分胁迫下品种间各参数变化幅度不同.除qNP外,其余各参数均为抗旱性越强降低幅度越小,而qNP则升高幅度越大.说明水分胁迫对冬小麦幼苗叶绿素荧光参数的影响与其抗旱性密切相关.更多还原

【Abstract】 Under the condition of hydroponics culture in climatron, the effects of water stress on chlorophyll fluorescence parameters of winter wheat seedlings of three varieties with different drought-resistance have studied. The results showed that under water stress, winter wheat seedlings variable fluorescence (Fv)、maximum fluorescence (Fm)、the ratio of the variable to maximum fluorescence (Fv/Fm),the ratio of the variable to minimal fluorescence (Fv/Fo) and the photochemical quenching coefficient (qP) decreased, while the minimal fluorescence(Fo) and non-photochemical quenching coefficient(qNP) raised. Analysis indicated that photosystem Ⅱ damaged, and primary light energy conversion of PSⅡ(Fv/Fm),potential activities of PSⅡ(Fv/Fo) decreased; photosynthetic electron transport,photosythetic primary reaction inhibited; heat disseminate which possess photoprotective effect increased. But each parameters varied difference between cultivars under water stress. Except for qNP, other parameters decreased smaller in wheat cultivars with strong ability of drought-resistance, whereas qNP increased greater. This implies that there was a closed relationship between the effects of water stress on chlorophyll fluorescence parameters of winter wheat seedlings and its drought-resistance.更多还原