盐碱危害植物生长的因素主要有以 下四个方面:Na＋、HCO3/CO３(碱性)、pH 和 CT。本文旨在探讨研究这四种因素中，哪种因素是影响羊草生长的主要限制因子。实验结果表明:四种胁迫因素对羊草不同部位生长影响不同。在中性盐处理条件下，Cｌ－对叶片、叶鞘、根茎、子株的生长起着主要的抑制作用，Na＋对根的生长起着一定的促进作用;在碱性盐处理条件下，碱容量是对羊草生长起着决定性作用的因素;对不同处理下的羊草各部分器官干重进行多元线性回归分析发现，上述四种危害植物生 长的因素与羊草各部分的生长情况有明显的线性相关关系，且各因素对羊草各部分器官生长的重要性不同。总体来讲，碱容量是对羊草生长影响最大的因素;各因素对叶片生长的重要性依次为碱容量、Cｌ－、pH、Na＋;对叶鞘生长的重要性依次为碱容量、Cｌ－、pH/Na＋;对根生长的重要性依次为碱容量、Na＋、Cｌ－/pH;对根茎生长的重要性依次为碱容量、pH、Cｌ－、Na＋;对子株生长的重要性依次为碱容量、pH/Cｌ－/Na＋(Cｌ－>Na＋)。

There are four stress factors that is harmful to the growth of plant in the stress and alkali stress as following,Na＋,HCＯ３－/CＯ3２－(alkalinity),pHand Cl－This article is for the purpose of discussing which kind of this four stress factors is the main limited factor that affect the growth of Leymus chinensis. The experimental result indicates that four stress factors have different influence on the different organ of the Leymus chinensis. Under the condition of Neutral salt,Cl－is the uppermost restraining stress factor to leaf blade,leaf sheath,rhizome and daughter plant growth,so is Na＋ to root.Under the condition of alkaline salt,alkali capacity plays a crucial role of restraining in the growth of Leymus chinensis. Carrying on an investigation in the data of Leymus chinensis' dry weight by multivariate linear regression analysis, we discovers that,these four stress factor above have the obvious linear correlation relations to the condition of growth of Leymus chinensis, but the weightiness of each factor is unlike to the various part of Leymus chinensis. Overall speaking, the alkali capacity is the most top-drawer factor to the growth of Leymus chinensis. Various factors on the importance of leaf growth is alkali capacity,Cl－pH,Na＋;on the importance of leaf sheath growth followed by alkali capacity,Cｌ－,pH/ Na＋;on the importance of root growth of the order of base capacity,Na＋,Cｌ－/pH;on the importance of root growth were alkali capacity,pH,Cｌ－,Na＋；pair the importance of plant growth were alkali capacity,pH/Cｌ－/Na＋(Cｌ－＞Na＋）.