摘要：土壤酸化已成为限制植物生长的主要因素之一，研究低pH对作物生长发育具有重要的科学意义。钙在植物生长和发育以及植物抗逆过程中具有重要作用，作为第二信使，胞内自由钙离子在植物很多生理和生化过程中扮演重要角色。已有研究显示，外源钙的施加能缓解植物在低pH下的伤害。本文以模式植物拟南芥（Arabidopsis thaliana）CAS反义植株（CASas）为材料，通过相关生理指标测定探讨钙及CAS在缓解钙胁迫对拟南芥抗氧化系统影响中的作用。主要取得以下结果：65400

1、 钙的添加可以促进拟南芥植株的生长，同时减缓低pH的抑制作用。

2、 钙的添加可以提高拟南芥植株叶绿素的含量。

3、 钙的添加可以提高拟南芥植株叶片的钙含量，同时减缓低pH对拟南芥植株叶片的钙含量的影响。

4、 钙的添加会降低拟南芥植株的MDA含量，同时减缓低pH对拟南芥植株的MDA含量的影响。

5、 钙的添加会导致拟南芥植株H2O2的含量在正常pH下增加、在低pH下降低，同时钙的添加可以减缓低pH对拟南芥植株的H2O2含量的影响。

总之， CASas在不同钙浓度条件下钙胁迫表现出的不同抗氧化响应可以推测钙及CAS可能参与了拟南芥响应低pH的过程中。

关键词：CAS拟南芥突变体，不同浓度的Ca，H2O2，干重，含水率

Abstract：Soil acidification has been one of the main factor of limiting the growth of plants.It has great scientific significance for the growth of plants to study low pH.Calcium plays a key role in plant growth and resistance.AS the second messenger,intracellular free calcium ion plays a key role in many physiological and biochemical process.Studies have shown that the exogenous calcium’s added can relieve the plant harm under the low pH..This article is based on the materials of the CAS antisense plants of Arabidopsis thaliana.The main results are summarized as follows by the determination of related physiological indexes to study the effect of calcium and CAS in relieving the calcium stress on the antioxidant system of Arabidopsis thaliana:

Firstly,the calcium’s added can improve Arabidopsis thaliana’s growth,which can also reduce the inhibition of low pH.

Secondly,the calcium’s added can improve the content of chlorophyll in Arabidopsis thaliana.

Thirdly, the calcium’s added can improve the content of calcium in Arabidopsis thaliana leaves,which can also reduce the effect on the content of calcium in Arabidopsis thaliana leaves under low pH.

Forthly, the calcium’s added can reduce the content of MDA in Arabidopsis thaliana,which can also reduce the effect of the content of MDA in Arabidopsis thaliana under low pH.

Fifthly, the calcium’s added can improve the content of H2O2 in Arabidopsis thaliana under the normal pH and reduce the content of H2O2 in Arabidopsis thaliana under the low pH,which can also reduce the effect of the content of H2O2 in Arabidopsis thaliana under the low pH.

In short, from the different antioxidant response of the calcium stress in different levels of calcium by CASas,we can infer that calcium and CAS may involve in the Arabidopsis thaliana’s response of low pH.

Keywords: the CAS mutant of arabidopsis,different concentration of calcium, hydrogen peroxide(H2O2), dry weight,rate of water content.

目录

1 前言 8

1.1 钙对作物的生长影响 8

1.1.1 钙的存在形态