松嫩平原两个生态型羊草实验种群对盐碱胁迫的生理响应

采用盆栽实验，对灰绿型和黄绿型两个生态型羊草(Leymus chinensis)在幼苗期分别用不同强度的NaCl、Na2CO3和混合盐碱胁迫，测定其叶片叶绿素含量、电解质外渗率和植株脯氨酸、Na／K等生理指标。结果表明，在3种盐碱胁迫条件下，灰绿型和黄绿型羊草的叶片叶绿素含量、电解质外渗率和植株脯氨酸、Na／K均与胁强之间呈直线y=a+bx变化，达到了显著或极显著水平，两个实验种群均具有耐盐碱能力，叶片叶绿素含量、电解质外渗率和植株脯氨酸、Na／K均有显著或极显著差异，它们在耐盐碱生理特性上已产生了分化，其中，灰绿型的耐盐碱能力强于黄绿型，本文为羊草生态型分化主导生态因子是土壤盐碱所致提供了的生理学证据。

Physiological response to salt-alkali stress in experimental populations in two ecotypes of Leymus chinensis in the Songnen Plains of China

The comparative study of physiological reaction to salt, alkali and mixed salt stresses in two ecotypes of grey-green and yellow-green of Leymus chinensis were made. At the stage of seedling, the content of chlorophyll and the leakage rate of electrolyte of leaves, free proline, Na/K of tillers were determined in planting containers with sands in two ecotypes by stress of salt, alkali and mixed salt of different concentrations. The results of quantitative analysis showed that the relationships between the content of chlorophyll and the leakage rate of electrolyte of leaves, free proline, Na/K of tillers and concentration of salt, alkali and mixed salt could expressed as linear equation, which were significant or obviously significant. There were capabilities of salt-alkali resistance in the physiological characteristics of two populations, but the capabilities of salt-alkali resistance were stronger in grey-green ecotype than in yellow-green ecotype. The differentiation of the content of chlorophyll, the leakage rate of electrolyte of leaves, free proline and Na/K of tillers were significant or obviously significant in two ecotypes under three kinds of salt stress. Physiological characteristics of salt-alkali resistance were significantly different in two ecotypes. The study provided physiological evidence for making sure that the main ecological factor was salt-alkali. It resulted in adaptive differentiation in Leymus chinensis ecotypes.