干旱胁迫对桑树生理生化特性的影响

以盆栽桑树为材料研究干旱胁迫对桑树生理生化特性的影响 ,结果表明 :在干旱胁迫下 ,随着胁迫的加强 ,抗旱性强的品种的过氧化物歧化酶 (SOD)、过氧化物酶 (POD)、过氧化氢酶 (CAT)活性提高 ,复水后下降迅速 ,而抗旱性弱的品种在一定胁迫下活性增加 ,严重胁迫时则下降 ,复水后下降趋势缓慢 ;抗旱性强的品种的叶片可溶性蛋白含量下降幅度小于抗旱性弱的品种 ,复水后抗旱性强的品种可溶性蛋白含量上升较快 ;抗旱性强的品种可溶性糖、脯氨酸的含量升高幅度大于抗旱性弱的品种 ,而丙二醛的质量分数升高幅度则小于抗旱性弱的品种 ,复水后抗旱性强的品种恢复较快 ;干旱胁迫下桑树叶片的净光合速率、蒸腾速率、水分利用效率下降 ,抗旱性强的品种净光合速率、水分利用效率高于抗旱性弱的品种。

Effect of Water Stress on Physiological and Biochemical Character of Mulberry

A study on the physiological-biochemical changes of different mulberry varieties under water stress was carried out,the results showed that the activity of SOD,POD and CAT of drought-resistant varieties changed from low to high and declined rapidly when watered again,that the activity of enzymes of drought-sensitive ones increased under a certain degree of drought stress,and declined under serious drought-stress and declined slowerly while watered again.The soluble protein content in leaf of drought-resistant varieties declined was less than that of drought-sensitive ones,and soluble protein content in leaf of drought-resistant varieties increased more rapidly than that of drought-sensitive ones when watered again.Soluble sugar and proline accumulation in drought-resistant varieties increased faster as compared with that in drought-sensitive ones under serious water stress.The content of MDA of drought-resistant varieties increased more slowly than that of drought-sensitive ones.The net photosynthetic rate and transpiration rate and water use efficiency of leaf declined under drought stress,and the net photosynthetic rate and water use efficiency of drought-resistant varieties was higher than that of drought-sensitive ones.