Abstract: In order to provide information on seed germination and establishment,the effects of salt stress on germination and physiological characteristics of Russian wildryegrass seed were studied using seven different salt concentrations,0%,0.3%,0.6%,0.9%,1.2%,1.5%,and 1.8%,of NaCl,Na₂CO₃,and NaHCO₃ under incubator.Seed germination percentage,germination energy,root and seedling growth rate,MDA content,and the activities of POD,SOD,and CAT were measured.The results indicate that the germination characteristics and root and seedling growth were significantly affected by salt stress.The MDA content,germination percentage and growth rate were significantly restrained by Na₂CO₃ stress,while the NaCl stress was minimum.The soluble sugar content and the activities of CAT,POD,and SOD reached maximum with the 0.6% Na₂CO₃ solution.The soluble sugar and CAT activity reached maximum with 1.5% NaCl solution,while the activities of POD and SOD with 1.2%.The effect of NaHCO₃ stress was at midway between Na₂CO₃ and NaCl.The order of salt stress impact from strong to weak on seed germination of Russian wildryegrass were Na₂CO₃>NaHCO₃>NaCl.

Key words: Russian wildryegrass, Salt stress, Germination characteristics,Physiological characteristics

摘要： 采用浓度为0%、0.3%、0.%、0.9%、1.2%、1.5%、1.8%的NaCl、Na₂CO₃、NaHCO₃单盐胁迫新麦草种子,通过种子萌发特性和生理特性的变化,研究其萌发时的耐盐能力和不同盐分对其危害程度,为新麦草(Psathyrostachys juncea(Fisch.) Nevski)在盐碱地的建植提供参考.结果表明:3种盐胁迫对新麦草种子的发芽率、发芽势、根生长速度和幼苗生长速度的影响差异明显.相同浓度下,Na₂CO₃胁迫时发芽率和生长速度受到显著抑制(P<0.05),MDA的积累量大.可溶性糖、CAT、POD、SOD在Na₂CO₃浓度为0.%时达到最大值;NaCl胁迫时MDA的积累量最小,发芽和生长受到的影响较小,可溶性糖和CAT在NaCl浓度1.5%时达到最大值,POD和SOD在浓度1.2%时达到最大值;NaHCO₃胁迫时受到的抑制介于中间.综合分析,3种盐对新麦草种子萌发影响的强弱顺序为:Na₂CO₃＞NaHCO₃＞NaCl.

关键词: 新麦草, 盐胁迫, 萌发特性, 生理特性