Abstract: In order to explore the mechanism of salt and drought tolerance of Kalidium foliatum,this study analyzed the effect of NaCl simulated salt stress,polyethylene glycol simulated drought stress and the interaction stress of salt-drought on seed germination and seedling growth of that species. The results showed that under single salt stress,the seed germination rate,vitality index,radicle length,germ length and fresh weight of K. foliatum seedlings increased first and then decreased,while the activities of superoxide dismutase,peroxidase and catalase were increased under 300 mmol·L^-1 NaCl. Similarly,under the single drought stress,the germination index,vitality index and radicle growth were decreased,and peroxidase and catalase activities of seedings were increased. Under the interaction stress of salt-drought,the germination rate,germination index and vitality index showed a decreasing trend with the increment of stress. The germination potential under 100 mmol·L^-1 NaCl +10% PEG was 2.13% higher than that in control. The radicle length,germ length,fresh weight and dry weight of the seedlings were increased under 100 mmol·L^-1NaCl+5% PEG compared to those in control. Salt stress was the main ecological factor affecting seed germination and seedling growth of K. foliatum as revealed from two-factor ANOVA and membership function analysis. This study could provide some reference for the improvement and ecological restoration of saline-alkali land in Hexi Corridor region.

Key words: Kalidium foliatum, Drought stress, Salt stress, Seeds germination, Antioxidant enzyme

摘要： 为探究盐爪爪(Kalidium foliatum)的耐盐旱机制，本研究分析了NaCl模拟盐胁迫、聚乙二醇(Polyethylene glycol，PEG)模拟干旱胁迫，以及盐旱交互胁迫对其种子萌发、幼苗生长的影响。结果表明：在单一盐胁迫时，种子发芽率、活力指数、胚根长、胚芽长、鲜重均呈先增后减趋势，在300 mmol·L^-1NaCl胁迫下幼苗的超氧化物歧化酶(Superoxide dismutase，SOD)、过氧化物酶(Peroxidase，POD)和过氧化氢酶(Catalase，CAT)活性增加。在单一干旱胁迫时，发芽指数、活力指数降低，胚根生长受到抑制，POD，CAT活性增加。盐、旱交互胁迫时，随着胁迫浓度的增加，发芽率、发芽指数、活力指数均呈下降趋势；在100 mmol·L^-1 NaCl +10% PEG胁迫下盐爪爪种子发芽势较对照增加2.13%，在100 mmol·L^-1NaCl+5% PEG胁迫下盐爪爪幼苗胚根长、胚芽长、鲜重、干重均较对照增加。通过双因素方差分析和隶属函数综合分析发现，盐胁迫是影响盐爪爪种子萌发和幼苗生长的主要生态因子。本研究为河西走廊地区盐碱地改良和生态修复提供一定的参考依据。

关键词: 盐爪爪, 干旱胁迫, 盐胁迫, 种子萌发, 抗氧化酶