不同地理种群大针茅生理生化特征的研究

A study on the physiological and biochemical characters of different Stipa grandis geographical populations

为了研究内蒙古地区主要建群种大针茅对环境的适应特性,本研究在内蒙古锡林郭勒草原选取5个大针茅分布的典型区域,分析了5个大针茅种群植株生理生化特征的差异以及这些性状之间的关联。结果显示,除叶绿素a/b外,其他生理生化性状在种群间均差异显著;性状间的Pearson相关性分析表明多数性状随环境的变化趋势是不一致的。进一步分析表明,大针茅叶绿素含量、丙二醛含量等指标对环境敏感,能够反映环境间的差异,其中,叶绿素含量能够反映植株的生长状态,而丙二醛含量能反映环境的干旱程度;保护酶系统对植株受胁迫的反应与植株的生长状态有关;渗透调节物质含量在同一种群内存在"互补"现象。本研究为更加深入地认识大针茅的适应机制和策略提供了科学数据和实验证据。

To analysis the adaptability of Stipa grandis to environmental conditions,five typical regions were selected in the Xilingol steppe.There were significant differences between populations for these characters except Chl a/b,but the frequencies of these traits along environmental variations were not consistent when tested by Pearson correlation analysis.Further analyses indicated： 1） The chlorophyll contents and MDA content were sensitive traits,and reflected the differences of environmental conditions.The chlorophyll contents reflected the status of S.grandis,and the MDA content reflected the drought status of their habitats.2） This was related to the response of protective enzymes to stress conditions and the growth status of S.grandis plants.3） Osmotic adjustment substance contents could be complementary within a population.The study provides scientific data and proofs to understand the adaptive mechanisms and strategies of S.grandis.