摘要
通过研究干旱和复水对麻疯树幼苗叶片的相对含水量、气体交换特性和叶绿素荧光特性的影响,结果表明:随着基质含水量的减小,麻疯树叶片相对含水量、净光合速率、蒸腾速率、气孔导度持续下降,胞间CO2浓度先下降后上升;最大荧光产量、PSII最大光量子产量、光化学猝灭系数和PSⅡ实际量子效率均呈现下降趋势,初始荧光有小幅上升。复水后,气体交换参数和荧光参数能很快恢复,植株可以成活,表明麻疯树有很强的自我调节能力,对基质干旱有极强的适应能力。当基质含水量从21.91%下降到15.22%时,各参数均无显著差异(P>0.05);当基质含水量从8.70%下降到6.83%时,各参数均有显著变化(P<0.05)。基质含水量为8.70%以上时,麻疯树碳同化能力降低的原因主要是气孔限制;基质含水量在8.70%以下时,光合效率的降低主要受非气孔限制。
Effects of drought and re-water on leaf relative water content （LRWC）, gas exchange characteristics and chlorophyll fluorescence characteristics of Jatropha curcas seedlings in different water conditions were studied. The results are as following： with the decreasing of soil volumetric water content （SVWC）, the leaf relative water content, photosynthetic rate （Pn）, transpiration rate （Tr）, stomatal conductance （Gs） of J. curcas declined gradually. Intercellular CO2 concentration （Ci） decreased at first, and then increased when SVWC was lower than 8.70%. Maximal fluorescence yield （Fm）, PSⅡ maximum quantum yield of light （Fv/Fm）, photochemical quenching （qP） and actual quantum yield of PSII photochemistry （ ΦSPS Ⅱ ） were shown a downward trend, while the initial fluorescence （Fo） slightly increased. After re-water, the gas exchange parameters and fluorescence parameters could be quickly restored and the plant could survive, indicating that J. curcas has strong self-regulating ability and strong adaptability to the drought stress. When SVWC was between 21.91% and 15.22%, parameters gas exc 6.81% hange and chlorophyll fluorescence were not significant （P 〉 0.05） . As SVWC declined from 8.70% to , parameters of gas exchange and chlorophyll fluorescence changed obviously. Therefore, it is suggested that when SVWC was above 8.70% ,the decreased carbon assimilation capacity of J. curcas was mainly due to stomatal limitation, and when SVWC was lower than 8.70%, the decreased carbon assimilation capacity of J. curcas was mainly due to non-stomatal limitation.
出处
《林业科学研究》
CSCD
北大核心
2010年第1期108-113,共6页
Forest Research
基金
中日技术合作四川省示范林营造项目(JICA)
国家科技部"十一五"科技支撑计划项目(2007BAD50B01)
四川省重点学科建设项目(SZD0419)资助
关键词
麻疯树
干旱胁迫
复水
气体交换参数
叶绿素荧光
Jatropha curcas L
drought stress
re-water
gas exchange parameters
chlorophyⅡ fluorescence
