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研究了土壤干旱条件下盆栽沙棘苗木生长、光合和水分关系的变化。结果表明 ,同样环境条件下 ,蒸腾速率随干旱胁迫程度加重而降低 ,而蒸腾日进程差异不大 ,均为单峰曲线 ,峰值出现在 1 1 :0 0 ;轻、中度干旱胁迫下沙棘叶含水量、水势、渗透势、膨压下降幅度较小 ,光合速率、侧枝生长速率保持在较高水平 ,能维持基本的生长量 ,表现出耐旱植物的生理特征 ;重度干旱胁迫使上述指标下降较显著 ,且长时间胁迫后 ,3 3 .3 %沙棘幼苗死亡
The changes of the growth, photosynthesis and water of seabuckthorn seedlings under soil drought were studied. The results showed that under the same environmental conditions, the transpiration rate decreased with the increase of drought stress, but the difference of transpiration day was not significant. Both of them were single peak curve with the peak at 11: 0 0. Under the mild and moderate drought stress, Water content, water potential, osmotic potential and turgor decreased less, and photosynthetic rate and collateral growth rate maintained at a relatively high level, which could maintain the basic growth and show the physiological characteristics of drought-tolerant plants. Severe drought stress decreased these indexes More significant, and after prolonged stress, 33.3% of seabuckthorn seedlings died