水分胁迫对美国山核桃叶绿素荧光参数的影响

Effect of Water Stress on the Chlorophyll Fluorescence Parameters of Pecan

研究水分胁迫对美国山核桃叶绿素荧光参数的影响,以探究水分胁迫损伤光合作用的机理.结果表明:在离体快速干旱水分胁迫处理方式下,美国山核桃叶片F o、Fm、F v/Fm、F v/F o、qP在离体6 h时均下降,但降低幅度不大;Y ield和qN在离体6 h时分别显著下降和上升,此说明美国山核桃苗遭遇水分胁迫时,叶片的PS II反应中心电子传递活性受到了一定程度的影响,但影响不大;光合电子传递速率明显下降,PS II反应中心耗散过剩光能的能力增强,其可作为品种耐旱能力的鉴定指标.

The effect of water stress on the chlorophyll fluorescence parameters of pecan was studied in order to probe the damage mechanism of water stress on photosynthesis. The results show that after detached drought treatment of 6 h, Fo, Fm, Fv/ Fro, Fv/ Fo, qP all took a slight but not significant decrease, and after the same treatment, yield decreased significantly while qN increased obviously. The results indicate that the electron-transmitted activity of PSⅡ reaction center was little affected and that the electron transporting rate decreased significantly while the ability of dissipation increased obviously. This can be used as the determination index to pecan＇s tolerance of drought.