中文摘要：

以2年生霸王为试验材料,用盆栽人工控制土壤水分,研究不同梯度土壤水分条件对霸王水分生理特征、丙二醛含量和细胞膜相对透性的影响。结果表明,与充足供水对照（土壤重量含水量为23%）相比,在严重干旱胁迫（土壤含水量为3%）20d和45d时,霸王叶水势和叶片相对含水量分别显著降低70.87%和45.54%、26.81%和12.66%;相应的叶片MDA含量和细胞膜相对透性分别显著增加33.81%和21.78%、17.51%和14.98%;严重干旱胁迫30d使得霸王叶片保水力显著下降;同时随着土壤干旱胁迫程度的增强,霸王日蒸腾耗水量持续下降,且严重干旱胁迫处理的蒸腾耗水量日变化为水平直线型,其余处理均为单峰型。研究发现,严重干旱胁迫下随着胁迫时间的延长,霸王叶水势和叶片相对含水量有增加趋势,而叶片MDA含量和细胞膜相对透性则有减小趋势,它能够通过自身的调节机制,逐渐改善叶片水分状况,降低细胞膜伤害程度,从而适应严重干旱环境。

英文摘要：

The two years old Zygophyllum xanthoxylum were choosed as materials,the water physiological characteristics,concentrations of MDA,membrane permeability in the leaves of Z.xanthoxylum were studied under the different level of soil water stress by pot experiment with controlling soil water.The results are as follows：Comparing with the treatment of enough water supply（CK,3% soil water content）,the leaf water potential and the leaf relative water content of two years old Z.xanthoxylum significantly decreased by 70.87% and 45.54%,26.81% and 12.66% respectively after 20 and 45 days severe drought stress（3% soil water content）.Correspondingly,the accumulation of MDA and the membrane permeability in the leaves of Z.xanthoxylum significantly increased by 33.81% and 21.78%,17.51% and 14.98% respectively under the same conditions.The leaf water holding capacity decreased significantly after 30 days severe drought stress comparing to the control.At the same time,the daily transpiring water-consumption decreased continuously with the increase of drought stress.It has also been revealed that the diurnal patterns of transpiring water-consumption was a horizontal line under the severe drought stress while one-humped curve under other treatments.As the severe drought stress continued,the leaf water potential and the relative leaf water content increased gradually while the concentrations of MDA and membrane permeability decreased comparing to the control.The results showed that some adaptive abilities of Z.xanthoxylum to severe aridity by the adjustment of itself could improve leaf water status and reduce the degree of cell membrane damage.