摘要
外源乙烯在一定的条件下明显抑制了超氧化物歧化酶（SOD)和过氧化氢酶（CAT）的活性，提高了超氧化物阴离子自由基和过氧化氢（H2O2）的产率，从而有效地诱导了内源乙烯产生的增加；外源和H2O2对乙烯产生的促进作用及外源活性氧清除剂对乙烯产生的抑制作用也为此提供了证明。乙烯对植物生理过程的调节机制之一就是通过影响活性氧清除酶活性，从而调节各种活性氧在体内的平衡。
After the treatment with various concentrations of ethrel for different time, the rate of production of ethylene in etiolated seedlingS of thede ra the activity of SOD and CAT,and the rate of production of and H2O2 were measured.Under some condihons, exogenous ethylene decreased the achvity of superoxide dismutase (an) and catalase (CAT), increased the rate of produchon of superoxide radical and H2O2,and induced effectively the increase of the evolution of endogenous ethylene.TIre is a threshold value for each of the above effects of exogenous ethylene: it was 10-2μmol/L and 10-1 μmol/L for the inhibihon of SOD and CAT respectively, and was 10-2μmol/L for the production of achve oxygen and of endogenous ethylene (FigS. 1～9).On the other hand, endogenous ethylene preduchon was increased by adding exogrnous (Na2S2O2) and H2O2. The scavenger of (SOD), and the scavenger of Hood (CAT) inhibited effectively the produchon of endogenous ethylene (Fig. 7 ). Exogenous ethylene can induce effectively the produchon of endogenous ethylene. because the involvement of and H2O2 in ethylene biosynthesis has been idenhfied, the Produchon of endogrnous ethylene induced by exogenous ethylene is caused POSSibly by an increase of the rate of produchon of and H2O2, and by a decrease of the activity of the SOD and CAT. TIs may be the mechanism of induchon of produchon of endogenous ethylene by exogrnous ethylene.
基金
国家自然科学基金
关键词
植物
乙烯
活性氧
合成
ethylene, SOD, CAT, superoxide radical, H_2O_2
