外源NADPH对NaCl胁迫下加工番茄幼苗生长及其抗逆生理指标的影响

摘要

采用营养液栽培法,以加工番茄品种“里格尔87-5”为材料,通过对NaCl胁迫下加工番茄幼苗叶片分别喷施5、10、15 μmol/L NADPH(还原型辅酶Ⅱ),研究外源NADPH对NaCl胁迫下加工番茄幼苗生长及其抗逆生理指标的影响.结果表明:外源喷施3种不同浓度的NADPH均能不同程度地改善NaCl处理下加工番茄幼苗的生长性状,提高根系活力和过氧化物酶(POD)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GPX)活性,降低电解质渗透率及丙二醛(MDA)、脯氨酸(Pro)、可溶性糖的含量.其中尤以NaCl胁迫下外源喷施10μmol/L NADPH的效果最佳.这说明外源NADPH通过促进盐胁迫下番茄幼苗植株渗透调节及清除活性氧的酶促系统的防御能力,降低膜脂过氧化,保护膜结构的完整性,从而有效缓解NaCl胁迫对番茄幼苗生长的抑制和提高了耐盐性.%By spraying tomato leaves with 5,10 and 15 μmol/L NADPH (reduced form of nicotinamide-adenine dinucleotide phosphate) respectively,a hydroponic experiment was conducted to investigate the effects of exogenous NADPH on the growth and physiology indexes of resistance stress of the processing tomato (Solanum lycopersicum cv.Ligeer 87-5) seedlings under salt stress.The results showed that the application of three different concentration of NADPH could improve the growth characters of tomato seedlings under NaCl treatment process,and improve the root activity and peroxidase (POD),superoxide dismutase (SOD),catase (CAT) and glutathione peroxidase (GPX) activity.Especially under NaCl stress,the effect of spraying 10 μ mol/L NADPH was best.These results indicated that exogenous NADPH alleviated salt-induced growth inhibition and enhanced salt-tolerance by promoting the osmotic adjustment capacity and the defense ability of antioxidant enzymes system,which could decrease membrane lipid peroxidation and protect the integrity of membrane structure in tomato seedlings under NaCl stress.