冬小麦抗旱性与膜脂过氧化的关系及其氮素调控机理

为了探明干旱条件下小麦拔节期膜质过氧化物质以及保护酶系之间关系及其氮素调控机理,在大田试验条件下,测定了两个不同抗旱性小麦品种郑麦9023(水地品种,抗旱性差)和长武134(旱地品种,抗旱性强)在不同施氮量条件下拔节期叶片MDA、H2O2含量以及SOD、CAT活性的变化.结果表明,抗旱性和小麦叶片的保护酶活性和膜质伤害物质的含量密切相关,而且受氮素营养的调控.抗旱品种相对不抗旱品种具有较高的SOD和CAT活性,而MDA和H2O2较低;MDA和H2O2含量随施氮量的增加呈现先降后升的趋势,而SOD和CAT则呈相反的变化趋势.适量施用氮素对抗旱性建立的贡献主要表现在其降低了超氧阴离子的产量,从而使SOD活性降低和CAT活性提高,使得H2O2和MDA含量维持在较低水平.

The relationship of drought resistance and cell membrane superoxide of winter wheat mediated by nitrogen

The content MDA and H2O2, the activity of SOD and CAT in the leaf of Zhengmai 9023 (drought-vulnerable wheat variety) and Changwu134 (drought – resistant wheat variety) which applied by difference quantity nitrogenous manure have investigated under field. The result showed that the drought-resistance relate to the leaf protectase activity and cell membrane superoxide significantly, moreover, mediated by nitrogen manure. The drought-resistant wheat variety has the higher protectase activity than drought-vulnerable wheat variety and lower MDA and H2O2 content; the dynamics of MDA and H2O2 content is reduced firstly and than increased as applied nitrogen manure quantity increased, it is contrary to protectase.