水分胁迫对三桠生理特性的影响

Influence of Water Stress on Some Physiological Characteristics of Edgeworthia Chrysantha

研究了盆裁三桠在人工控制土壤水分条件下某些生理特性的变化。结果表明：在土壤干旱条件下，三桠叶片自由水锐减，而束缚水含量有所增曹加；叶绿素含量及净光合速率随着土壤干旱的加重而下降；呼吸消耗增加，光合作用效率降低；蒸腾速率明显下降，在重度干旱时下降达６６．６％，水分利用效率有所提高；游离脯氨酸积累较少。这说明三桠对水分胁迫的适应能力较差。

The effects of water stress on some physiological characteristics of Edgeworthia chrysantha weretested.The results were as follows :undcr drought soil condition,loss of free water caused sharpdecrease of water contents in leaves,but the bend water increased slightly;the rate of netphotosynthesis evidently declined as soil water stress developed,and meanwhile the respiraryassumption tended to increase,somewhat associated to the decrease of chlorophyll content in theleaves.Under severe drought condition,the rate of transpiration decreased sharply,merely33.4%as much as that of the control.Tlle accumulation of free pro content in the leaves ofEdgeworthia chrysantha was comparatively low,indicating its poor adaptability to water stress.