钙对NaCl胁迫下玉米幼苗保护酶活性等生理特性的影响

Effect of calcium on protective enzymes activeness and physiological characteristics of maize seedlings under salt stress

采用水培法研究了不同浓度钙对盐胁迫下玉米幼苗生长、叶绿素含量、游离氨基酸含量及保护酶活性等生理特性的影响。结果表明适量的Ca^2＋（4mmol／L）供应能有效促进玉米生长，抑制叶绿素含量降低，降低细胞膜透性，提高玉米叶片和根系中的SOD和POD活性，随着Ca^2＋浓度增加根系中CAT活性增加，叶片CAT活性有所下降。增加Ca^2＋浓度，根系中游离氨基酸含量和可溶性蛋白含量呈现出先升高（2～4mmol／L）后降低（6mmol／L）趋势，叶片中可溶性蛋白含量随Ca^2＋浓度增加而降低。表明适量的Ca^2＋供应可提高玉米幼苗耐盐性。

A solution culture was conducted to study the effect of Ca^2＋ on the growth of maize seedlings, chlorophyll content, free amino acids content, the activeness of several protective enzymes and other physiological characteristics. The results show that the Ca^2＋ concentration at 4 mmol/L could obviously increase plant growth and restrain the decrease of chlorophyll content reduced permeability of cell membrane, and enhance SOD and POD activity in leaves and roots. With the increase of Ca^2 ＋ concentration, the CAT activeness in roots was increased but that in leaves was decreased. The free amino acids and soluble protein content in roots in- creased in terms of 2 - 4 mmol/L of Ca^2 ＋ concentration but decreased in that of 6 mmol/L. Soluble protein in leaves was decreased with the increase of Ca^2 ＋ concentration. The above results suggested that the appropriate Ca^2 ＋ supply can enhance the salt tolerance in maize growing in salt stress.