油菜素内酯对氯化钠胁迫下黄瓜幼苗的缓解效应

Alleviation effects of brassinolide on cucumber seedlings under NaCl stress.

研究了2,4-表油菜素内酯(EBR)对氯化钠胁迫下黄瓜幼苗叶片光合作用及抗氧化系统的影响.结果表明:与对照相比,氯化钠胁迫导致黄瓜幼苗叶片超氧阴离子产生速率、过氧化氢和丙二醛含量、细胞膜透性显著升高,净光合速率、气孔导度、蒸腾速率、胞间CO_2浓度显著下降,幼苗生长显著受抑.EBR可提高黄瓜幼苗叶片超氧化物歧化酶、过氧化物酶、过氧化氢酶等抗氧化酶活性,降低超氧阴离子产生速率、过氧化氢和丙二醛含量及细胞膜透性,维持良好的光合性能,从而促进幼苗生长,有效缓解氯化钠胁迫造成的伤害.

This paper studied the effects of 2,4-epibrassinolide （EBR） on the photosynthesis and antioxidant system of cucumber seedling leaves under NaC1 stress. As compared with the control, NaC1 stress increased the leaf superoxide anion production rate, hydrogen peroxide content, malon- dialdehyde content, and cell membrane permeability while decreased the leaf net photosynthetic rate, stomatal conductance, transpiration rate, and intercellular COz concentration significantly, and inhibited the seedlings growth significantly. Applying EBR could increase the activities of leaf superoxide dismutase, peroxidase, and catalase, decrease the leaf superoxide anion production rate, hydrogen peroxide content, malondialdehyde content, and cell membrane permeability, make the leaves keep a higher photosynthetic rate, and thus, promote the seedlings growth, being able to effectively alleviate the damage of NaC1 stress.