油菜素内酯对硝酸钙胁迫下黄瓜幼苗抗氧化系统及可溶性蛋白表达的影响

Effects of Brassinolide on the Anti-oxidant System and Soluble Protein Expression in Cucumber Seedlings under Calcium Nitrate Stress

目的:研究硝酸钙胁迫下24-表油菜素内酯(EBR)对黄瓜幼苗抗氧化性能及可溶性蛋白表达的影响。方法:通过单因素随机区组设计,从其抗氧化性能及可溶性蛋白表达的变化来探讨EBR对硝酸钙胁迫下黄瓜幼苗的影响。结果:与对照相比,硝酸钙胁迫导致黄瓜幼苗的丙二醛含量及细胞膜透性显著提高了115.1%和105.6%,膜脂过氧化加剧,黄瓜根系中可溶性蛋白含量降低且至少有35种蛋白发生明显变化,而叶片的可溶性蛋白含量升高且至少有29种蛋白发生明显变化;而硝酸钙胁迫下喷施EBR后黄瓜幼苗的SOD、POD、CAT分别比单纯的硝酸钙胁迫增加了20.2%、20.3%、34.4%,并提高了其可溶性蛋白含量及其表达的变化幅度。结论:24-表油菜素内酯可通过调节硝酸钙胁迫下黄瓜幼苗抗氧化性、可溶性蛋白含量及其表达,进而降低其膜脂过氧化程度,以缓解硝酸钙胁迫对植株的伤害。

Objective： A hydroponic experiment was conducted to study the effects of 24 - epibrassinolide （EBR） on the antioxidant system and soluble protein expression in cucumber seedlings under calcium nitrate stress. Method： Through the single factor randomized block design, from the change including the oxidation resistance and soluble protein expression to explore EBR effects on cucumber seedlings under calcium nitrate stress. Result： Compared with the control, Calcium nitrate stress leads to the MDA content and cell membrane permeability of cucumber seedlings significantly increased by 115.1% and 105.6%, increased membrane lipid peroxidation and decreased soluble protein content in roots, but increased in leaves. And calcium nitrate stress noticeable affected the expression of 35 soluble proteins in roots and 29 proteins in leaves at least. After the stress of calcium nitrate spray EBR, cucumber seedlings SOD, POD, CAT respectively than pure calcium nitrate stress increased by 20. 2%, 20.3%, 34.4% and increased variation width of soluble protein content and expression. Conclusion： Ex- ogenous EBR could alleviate the inhibition of calcium nitrate stress on cucumber seedlings by adjusting the protective enzyme activity and changing the soluble protein content and expression, and reducing membrane lipid peroxide level under calcium nitrate stress.