【摘要】 用PEG-6000模拟水分胁迫处理糙草(Asperugo procumbensL.)幼苗,测定生理指标,研究其对水分胁迫的生理适应性。结果表明:5%PEG和20%PEG胁迫处理1d后,叶片RWC、CHL含量,MDA和膜相对透性及脯氨酸含量变化不大,抗氧化酶活性升高;5%PEG和20%PEG胁迫处理5d后叶片RWC下降为对照65%、43%,CHL含量下降为对照的53%、46%,MDA和膜相对透性及脯氨酸含量显著升高,抗氧化酶活性显著降低,并低于处理前水平。实验表明糙草幼苗在水分胁迫下叶片持水力较低,在短时间水分胁迫下可通过抗氧化酶之间的相互协调在一定时期能维持活性氧代谢平衡,并阻止或减弱膜脂过氧化的伤害,但随着处理时间的延长,抗氧化酶活性显著降低,膜脂过氧化作用增加,且叶绿素合成遭到破坏。更多还原

【Abstract】 In this study,the mechanism of physiological adaptation of Asperugo procumbens.L under different water stress by polyethylene glycol was examined.The result showed that,after one day 5% PEG and 20% PEG stress,relative water content(RWC),CHL content,MDA content and Membrane electrolyte leakage did not change markedly,while antioxidant enzymes activities hoist,After five days treatment with 5%PEG and 20%PEG,RWC decreased to 65% and 43% of the control,CHL decreased to 53% and 46% of the control,MDA content,Membrane electrolyte leakage and praline content hoist markedly,while antioxidant enzymes activities decreased markedly after treatment.The experiment indicated that young Asperugo procumbens L.’s ability of holding moisture is low under water stress,Asperugo procumbens L.maintained active oxygen metabolism under the short time moisture content coercion by coordination of several antioxidant enzymes’ activities to prevent or decrease the damage of superoxide radicals,but as water stress aggravated,antioxidant enzymes activities notably decreased,and the damage of superoxide radicals increased,the chlorophyll synthesis is destructed,too.更多还原