外源一氧化氮对渗透胁迫下冬瓜幼苗生理特性的影响

Effects of Exogenous Nitric Oxide on Physiological Characteristics of Wax Gourd Seedlings under Osmotic Stress

采用0.1～0.5mmol/LSNP处理,研究外源NO对20%PEG-6000渗透胁迫下冬瓜幼苗生理特性的影响.结果表明:0.1mmol/LSNP处理能显著缓解20%PEG-6000的胁迫伤害,使叶片MDA含量降低62.65%,相对电导率降低28.09%,Pro含量提高14.35%,POD、CAT和SOD活性分别提高1.46倍、41.34%和14.01%.与0.1mmol/LSNP处理相比,0.3,0.5mmol/LSNP处理缓解叶片氧化损伤和提高保护酶活性的作用明显或显著降低,0.5mmol/LSNP抑制POD与SOD活性.

SNP （sodium nitroprusside） was used in this experiment at three concentrations （0.1,0.3,0.5 mmol/L） to investigate the effects of exogenous nitric oxide on the physiological characteristics in osmotically stressed wax gourd （Benincasa hispida Cogn.） seedlings.20% PEG-6000 was used to produce the osmotic stress,under which the effects of SNP were measured on oxidative damage to the leaves and protective enzyme activities in wax gourd.The results showed that the damage to wax gourd caused by the osmotic stress of 20% PEG-6000 was significantly reduced in the presence of 0.1 mmol/L SNP.Specifically,the level of malondialdehyde （MDA） in the leaves decreased by 62.65%;the relative conductivity in the leaves decreased by 28.09%;the proline content and enzyme activities of POD,CAT and SOD in the leaves increased by 14.35%,146%,41.34% and 14.01%,respectively;When the concentration of SNP increased to 0.3 and 0.5 mmol/L,the oxidative damage to the leaves sustained and the protective enzyme activities decreased,and 0.5 mmol/L SNP suppressed the activity of POD and SOD.