外源NO对低温胁迫下铁皮石斛抗氧化酶的影响

Effects of Exogenous NO on Antioxidant Enzymes of Dendrobium candidum under Low Temperature Stress

文章以一年生铁皮石斛苗为试验材料,研究不同浓度(0.01mmol/L、0.05mmol/L、0.10mmol/L、0.15mmol/L)硝普钠(SNP)对低温胁迫(0℃,12h)下铁皮石斛(Dendrobium officinale)叶片抗氧化酶活性及基因表达的影响,旨在探讨外源NO与铁皮石斛抗冷性的关系。结果表明,低温胁迫下,0.10mmol/LSNP处理铁皮石斛,叶片SOD、CAT、POD活性与对照组相比显著增加,MDA含量和相对电导率显著降低。叶片SOD、CAT、POD基因表达荧光定量PCR分析发现,低温胁迫下0.10mmol/LSNP处理铁皮石斛,上调叶片SOD、CAT、POD基因表达,3基因的表达模式存在差异。外源NO处理可以上调SOD、CAT、POD表达,增强SOD、CAT、POD活性,有利于缓解铁皮石斛低温胁迫。

In this paper, annual Dendrobium candidum seedlings were used as experimental materials to study sodium nitroprusside (SNP) at different concentrations (0.01 mmol/L, 0.05 mmol/L,0.10mmol/L, 0.15 mmol/L).Effects of low temperature stress on antioxidant enzymes activity and gene express ion in leaves of Dendrobium officinale were studied in order to i nvestigate the relationship between exogenous NO and iron bark.The relationship between cold resistance of Dendrobium. The results showed that the activities of SOD, CAT and POD in leaves of Dendrobium officinale treated with 0.10 mmol/LSNP increased significantly under low temperature stress compared with the control group.MDA content and relative conductivity decreased significantly. Fluorescence quantitative PCR analysis of SOD, CAT and POD gene expression in leaves showed that Dendrobium officinale was treated with 0.10 mmol/LSNP under low temperature stress.The expression patterns of SOD, CAT and POD genes in leaves were different. Exogenous NO treatment can up-regulate SOD, CAT, POD expression, and enhance SOD,CAT, POD expression.POD activity could alleviate the low temperature stress of Dendrobium officinale.