外源AsA、GSH对Cd胁迫下石竹幼苗生长的影响

应用生态学报

外源AsA、GSH对Cd胁迫下石竹幼苗生长的影响

丁继军^1,2,刘柿良¹,潘远智^1**,李丽³

(¹四川农业大学风景园林学院，成都 611130； ²长江三峡实业有限公司，湖北宜昌 443002； ³西南林业大学林学院，昆明 650224)

出版日期:2014-02-18 发布日期:2014-02-18

Effects of exogenous AsA and GSH on the growth of Dianthus chinensis seedlings exposed to Cd.

DING Ji-jun^1,2, LIU Shi-liang¹, PAN Yuan-zhi¹, LI Li^3

(¹College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611130, China; ²Three Gorges Industrial Co. Ltd., Yichang 443002, Hubei, China; ³College of Forestry, Southwest Forestry University, Kunming 650224, China)

Online:2014-02-18 Published:2014-02-18

摘要/Abstract

摘要： 采用温室盆栽试验，研究了不同浓度(0、20、40、60、80、100 mg·L^-1)的外源抗坏血酸(AsA)与谷胱甘肽(GSH)对50 mg·kg^-1镉(Cd)胁迫下石竹幼苗生长的影响.结果表明: 50 mg·kg^-1 Cd显著抑制了石竹幼苗的生长，适宜浓度的外源AsA能够缓解Cd对石竹幼苗生长的胁迫，显著提高其生物量、株高、分蘖数、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)等抗氧化酶活性，以及AsA和GSH含量,但随着外源AsA浓度的增加，缓解效应下降，甚至产生促氧化效应；外源GSH可以及时补充Cd胁迫下石竹幼苗体内的非酶抗氧化剂，但抗氧化酶活性变化相对较小，其缓解Cd毒害的主要机制可能是促进根系中金属螯合肽(PCs)的合成，增加其与Cd的螯合，从而降低石竹幼苗体内Cd含量.研究表明，35～45 mg·L^-1的外源AsA和55～65 mg·L^-1的外源GSH都能很好地缓解石竹幼苗Cd毒害，且前者效果优于后者.

Abstract: A pot experiment was carried out under greenhouse condition to investigate the effects of different concentrations (0, 20, 40, 60, 80 and 100 mg·L^-1) of exogenous AsA, GSH on Dianthus chinensis seedlings which were stressed by 50 mg·kg^-1 Cd in the soil. The results indicated that 50 mg·kg^-1 of Cd significantly inhibited the growth of D. chinensis seedlings. An appropriate concentration of exogenous AsA significantly improved the biomass, plant height, tiller number, GAT and APX activities, and AsA and GSH contents. However, with the increase of exogenous AsA concentration, the ameliorating effect decreased and prooxidant effect occurred. Exogenous GSH could replenish the nonenzymatic antioxidants of D. chinensis seedlings, but the changes of antioxidant enzyme activities were relatively slight. The main mechanisms of GSH to alleviate Cd toxicity might be promoting root PCs synthesis, thereby reducing the Cd concentration in the seedlings. Both 35-45 mg·L^-1 exogenous AsA and 55-65 mg·L^-1 exogenous GSH could alleviate the Cd toxicity on D. chinensis seedlings, and the former was superior to the latter.

丁继军1,2,刘柿良1,潘远智1**,李丽3. 外源AsA、GSH对Cd胁迫下石竹幼苗生长的影响[J]. 应用生态学报.

DING Ji-jun1,2, LIU Shi-liang1, PAN Yuan-zhi1, LI Li3. Effects of exogenous AsA and GSH on the growth of Dianthus chinensis seedlings exposed to Cd.[J]. Chinese Journal of Applied Ecology.