Abstract: Tall fescue seedlings under shade stress were treated with sodium nitroprusside(SNP) as the donor of exogenous nitric oxide(NO). Chlorophyll contents, membrane permeability, malondialdehyde MDA) contents, antioxidant enzyme activities and Proline contents in the leaves of tall fescue under shade stress were reported here. Results showed that exogenous nitric oxide(NO) could increase chlorophyll contents, alleviate increasing of membrane permeability and MDA contents, promote accumulation of Proline contents and increase superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities of tall fescue under shade stress significantly(P<0.05). Membrane permeability, MDA contents, CAT activities and proline contents of TarHeelⅡhad significant variation under shade stress. Effects of exogenous nitric oxide on TarHeel Ⅱ were more than other varieties. Exogenous nitric oxide could protect tall fescue from shade stress and there were inherent differences between observed varieties.

Key words: Tall fescue, Shade stress, Nitric oxide(NO), Membrane permeability, Antioxidant enzyme system

摘要： 用外源一氧化氮(NO)供体硝普钠(SNP)处理遮荫胁迫下的2个高羊茅(Festuca arundinacea)品种,探讨外源NO对遮荫胁迫下其叶绿素含量、膜透性、丙二醛(MDA)含量、抗氧化酶活性及脯氨酸(Pro)含量的影响。结果表明:外源NO可以显著提高遮荫胁迫下高羊茅叶片的叶绿素含量(P<0.05),减弱质膜相对透性的增加,减缓膜质过氧化产物MDA含量的升高,促进Pro的积累,提高超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性(P<0.05)。遮荫胁迫下高羊茅品种踏火二号的电解质渗透率、MDA含量、CAT活性和Pro含量的变化显著(P<0.05),NO的作用效果更明显。表明外源NO对遮荫胁迫下的高羊茅具有一定的保护作用,且存在品种差异。

关键词: 高羊茅, 遮荫, 一氧化氮, 膜透性, 抗氧化酶系统