土壤水分胁迫条件下 ,盆栽新红星幼树叶片相对含水量、水势降低 ,叶面积缩小 ,叶绿素含量下降 ,气孔阻力增大 ,蒸腾速率降低 ,从而使光合速率下降。光合速率下降幅度 :重度水分胁迫中度水分胁迫 >轻度水分胁迫。轻度水分胁迫光合速率与对照之间差异不显著 ;中度、重度水分胁迫与对照之间差异均达显著水平。 Under the condition of soil water stress, the relative water content, water potential, leaf area, chlorophyll content, stomatal resistance and transpiration rate decreased in young leaves of potted Neocupro everglades, so the photosynthetic rate decreased. Decrease of photosynthetic rate: Severe water stress Moderate water stress> mild water stress. There was no significant difference between the photosynthetic rate of mild water stress and the control; the difference between moderate and severe water stress and the control reached significant level.