干旱胁迫下La^(3+)在小麦幼苗叶片受伤害中的作用研究  

The research on the effect of La^(3+)in the damage of wheat seedling leaves under drought stress

作　　者：侯玉芸[1] 敬兰花[1] 曾福礼[1] 

机构地区：[1]兰州大学生命科学学院,兰州730000

出　　处：《西北植物学报》2001年第6期1134-1141,共8页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金资助项目 ( 39770 1 83)

摘　　要：低浓度 L a3 +叶喷小麦整株幼苗后 ,随着干旱处理时间的延长 ,除对叶片相对含水量没有影响外 ,却对叶细胞膜相对透性、丙二醛产生量、O- ·2 和 H2 O2 的产生速率均有影响 ,其变化趋势与不加 La3 + 叶喷的正常和干旱处理的小麦整株叶片相比较 ,变化曲线上升部分却下降 ,下降部分却略有升高。表明 L a3 +可抑制干旱胁迫后引起的小麦幼苗叶片细胞膜相对透性增加 ,降低干旱胁迫引起的膜脂过氧化产物 MDA含量 ,抑制 O- ·2 产生速率 ,减少叶片中 H2 O2积累 ,阻止 Fe2 + 的继续生成 ,限制了由 Fe2 + 催化的 Haber- Weiss和 Fenton反应中底物 O- ·2 和生成· OH的生成速率 ,使小麦叶片中· OH产生量相对减少 ,降低了叶细胞膜脂过氧化水平 ,减轻膜伤害 ,起到了保护。After spraying low concentration La 3+ on the wheat seedling leaves,with the prolonging of the drought stress,there was no effect on the leave relative water content but there was effect on the leave cell membrances relative penetrability,MDA production and the rate in the produce of O -· 2 and H 2O 2,compared with the wheat spraying no La 3+ on its leaves under normal control and drought stress control,when La 3+ was added the change tendency was different from the wheat that no La 3+ was added.Contrary to the ascendant part of the change curve of no La 3+ ,the change curve of low concentration La 3+ went down,on the other hand,the descend part of the change curve of no La 3+ now rised.This result showed La 3+ could inhibit the increase of the wheat seedling leaves cell membrances relative penetrability after drought stress reduce the content of the membrane lipid peroxidation product MDA,inhibit the produce rate of O -· 2,reduce the H 2O 2 accumulation in leaves,provent the produce of Fe 2+ ,limit the produce rate of O -· 2 and ·OH which were seporately the reactant and product in the Fe 2+ catalysised Haber weiss rection and Fenton realtion,reduced the production content of ·OH in wheat leaves relatively,cut down the level of the leave membrane lipid peroxidation,lighted membrane damage,provented membrane from being damaged by drought stress.

关 键 词：小麦叶片 稀土元素 干旱胁迫 膜脂过氧化 ·OH自由基 

分 类 号：Q945.78[生物学—植物学] S512.1[农业科学—作物学]