钙对盐胁迫下红海榄幼苗生长及膜脂过氧化的影响

Effect of Calcium on the Growth and Lipid Peroxidation of Rhizophora stylosa Seedlings under Salt Stress

[目的]提高红海榄抗盐胁迫的能力。[方法]用添加5、15、25mmol／LCaCl2的培养基培养盐胁迫下的红海榄幼苗，研究钙对盐胁迫下红海榄幼苗生长及膜质过氧化的影响。[结果]根及叶片的鲜重在5mmol／L钙处理时明显高于对照和单独盐处理，15mmol／L钙处理达到峰值。5mmol／LCa^2＋处理根的SOD活性一直维持较高水平而达到最大值，15mmol／LCa^2＋处理叶片的SOD活性最大，4个月后25mmol／LCa^2＋处理的最大，比对照和盐处理分别高28．49％和23．32％。5mmol／LCa^2＋处理根的MDA含量一直雏持较低水平而达到最小值。15mmol／LCa^2＋处理叶片的MDA含量最低，2个月后明显低于其他组，仅为单独盐处理的46、98％。钙能有效提高红海榄幼苗根及叶片的鲜重和SOD活性，降低丙二醛含量，提高其耐盐性。[结论]5～15mmol／LCa^2＋有效提高了红海榄幼苗抗盐胁迫的能力。

[Objective] The study aimed to enhance the resistance capability of Rhizophora stylosa to salt stress. [Method] The R. stylosa seedlings under salt stress was cultured on the medium added 5, 15 and 25 mmol/L CaCl2 to study the effect of Ca^2＋ on the growth and lipid peroxidatiou of R. stylosa seedlings under salt stress. [Result] The fresh weights of root and leaf treated with 5 mmol/L Ca^2＋ were obviously higher than that in CK and the alone salt treatment, and reached peak value in the treatment with 15 mmol/L Ca^2＋ . SOD activity in root treated with 5 mmol/L Ca^2＋ was always sustained at higher level and reached maximum, that in leaf treated with 15 mmol/L Ca^2＋ was highest and that in leaf treated with 25 mmol/L Ca^2＋ was highest after 4 months, being 28.49% and 23.32% higher than that in CK and salt treatment resp. MDA content in root treated with 5 mmol/L Ca^2＋ was always sustained at lower level and reached minimum, and that in leaf treated with 15 mmol/L Ca^2＋ was lowest and obviously lower than that in the other groups after 2 months, being only 46.98% of that in alone salt treatment. Ca^2＋ could enhance the fresh weight and SOD activity of root and leaf of R. stylosa seedlings effectively, reduce MDA content and enhance salt resistance of R. stylosa seedlings. [Conclusion] Ca^2＋ in 5 - 15 mmol/L enhanced the resistance capability of R. stylosa seedlings to salt stress effectively.