西藏裸大麦叶片旱促衰老与活性氧代谢的关系

Relativity of Acceleration of Senescence of Naked Barley Leaves in Duced by Drought and Activity Oxygen Metabolism in Tibetan

干旱诱导裸大麦叶片衰老中，叶绿素、蛋白质含量和过氧化氢酶（ＣＡＴ）、超氧化物歧化酶（ＳＯＤ）活性下降，水势降低；膜透性、过氧化物酶（ＰＯＤ）活性及脂类过氧化产物丙二醛（ＭＤＡ）迅速上升。外源自由基清除剂半胱氨酸、二苯胺、巯基乙醇、苯甲酸钠及α－生育酚处理可抑制叶绿素、蛋白质含量和过氧化氢酶、超氧化物歧化酶活性，水势下降，同时阻止膜透性、过氧化物酶活性及脂类过氧化产物丙二醛的上升。叶片旱促衰老中活性氧起重要作用。

While the drought was accelerlerated senescence of naked barley leaves,thechlorophyll,content of protein,activities of catalase(CAT)and superoxide dismutase(SOD)decreased.But drought produced a markable increase of the level of permeability ofplasma membrane,activity of peroxidase(POX)malondialdehyde(MDA).The resultsshowed that decreasing the level of chlorophyll,content of protein,and activities of CATand superoxide dismutase(SOD)by thp pretretment with free radical-scavengers of namelycysteine,diphenylamine,rnercaptoethand,sodium benzoate and α-tocopherol,and increasingpermeability of plasma membrane,activity of POX,MDA activity oxygen is important in ac-celeration of senescence of leaves by drotight.