一氧化氮对水分胁迫下玉米种子萌发及幼苗生理特性的影响

Effects of nitric oxide on seed germination and physiological reaction of maize seedlings under water stress

关键词:  一氧化氮(NO)  硝普钠(SNP)  水分胁迫  玉米  种子萌发  幼苗生理特性

Key words:  nitric oxide(NO)  sodium nitroprusside(SNP)  water stress  maize  seed germination  seedling physiological reaction

摘要:

以0.4 mol/L的甘露醇（M）模拟水分胁迫状况，研究了外源一氧化氮(NO)供体硝普钠(SNP)对水分胁迫下玉米种子萌发、幼苗生长和生理特性的影响。结果表明：(1)水分胁迫下，玉米种子萌发和幼苗生长受到抑制，叶片丙二醛（MDA）含量、质膜相对透性、脯氨酸含量均显著增加；(2)SNP能显著提高水分胁迫下玉米种子的发芽率、发芽势、发芽指数和活力指数，增加玉米幼苗的根长、茎长、根重和整株干重，抑制水分胁迫下玉米幼苗叶片MDA含量的上升，降低叶片质膜相对透性，降低脯氨酸含量。其中以100 μmol/L和200 μmol/L SNP对水分胁迫的缓解效果最佳。

Abstract:

The effects of sodium nitropprusside(SNP)，an exogenous nitric oxide donor at different concentrations，on the seed germination，growth and physiological reaction of maize seedlings under 0.4mol/L manntol(M)stress were studied. The results showed that：(1)The water stress inhibited significantly the maize seed germination and growth of seedlings，increased significantly the malondialdehyde(MDA)content，cell membrane permeability and content of proline；(2)The treatments with SNP at different concentrations could promote the germination rate，germination energy，index of germination and index of vigor of maize seeds，increased the root length，stem length，root height，dry weight，relative water content and carotenoid contents of maize seedlings，inhibited significantly the MDA content，cell membrane permeability and the content of proline of maize seedlings under water stress. It was shown that exogenous nitric oxide had abating effect on depressed seed germination and growth of maize seedlings，could improve the antioxygen ability of maize seedlings，debasing lipid peroxidation and protect plasma membrane from being destroyed during the water stress to enhance the drought resistance of plants under water stress and the best abating effect occurred with the SNP concentrations set at 100 μmol/L and 200 μmol/L.