西北林学院学报2024，Vol.39Issue(4)：1-14,14.DOI:10.3969/j.issn.1001-7461.2024.04.01
褪黑素对镉胁迫下蒿柳抗氧化系统及叶肉细胞超微结构的影响
Effects of Melatonin on Antioxidant System and Mesophyll Cell Ultra-microstructure in Salix viminalis Under Cadmium Stress
摘要
Abstract
As a woody plant with short rotation,Salix viminalis demonstrates the potential remediation ca-pacity of cadmium(Cd)pollution,but it has poor tolerance for high concentration Cd.Improving its growth status becomes the key for increasing Cd pollution remediation efficiency.This study aimed to in-vestigate the effects of melatonin(MEL)on antioxidant system of S.viminalis exposed to high concentra-tion Cd,which helps to further reveal the physiological mechanism of MEL regulation on antioxidant sys-tem in woody plants exposed to Cd,to provide practical guidance for MEL application in phytoremediation.Cutting seedlings of S.viminalis with the same clone were taken as experimental materials.Four treat-ments were set:blank(BT),foliar application with MEL(MT),Cd stress(CT),and foliar application with MEL followed by Cd stress(MCT)to examine the regulatory mechanism of MEL on reactive oxygen spe-cies level,lipid peroxidation degree,and antioxidant system in S.viminalis under Cd stress,and to investi-gate the protect effect of MEL on mesophyll cell ultra-microstructure.The root hydrogen peroxide and ma-londialdehyde(MDA)contents of S.viminalis exposed to Cd decreased by 69％and 28％,catalase(CAT)activity decreased by 49％on the 7th day after treatment;while by using MEL,CAT,glutathione reductase(GR),monodehydroascorbate reductase(MDHAR)activity of the leaf increased by 120％,33％,and 23％respectively,root superoxide dismutase(SOD)and GR activity increased by 60％and 36％.The superoxide anion and MDA contents in the leaf exposed to Cd increased by 70％and 81％,leaf MDHAR activity de-creased by 47％,and mesophyll organelles disappeared;the hydrogen peroxide and MDA contents in root increased by 124％and 69％,MDHAR activity decreased by 36％on the 21st day after treatment.By using MEL,superoxide anion and MDA contents of the leaf decreased 25％and 36％,SOD,peroxidase(POD),CAT,GR,and MDHAR activity in the leaf increased by 26％,34％,22％,27％,and 141％,respectively,mesophyll cell structure was intact;the hydrogen peroxide and MDA contents of the root decreased 35％and 40％,POD,GR,and glutathione S-transferase(GST)activity in root increased by 25％,33％,and 10％,respectively.It is inferred that MEL improves antioxidant capacity of S.viminalis exposed to Cd by increasing peroxidase,root superoxide dismutase,and leaf catalase activity;by enhancing monode-hydroascorbate reductase activity to increase ascorbic acid content;by increasing glutathione content to en-hance the activity of glutathione reductase and glutathione S-transferase and promote the AsA-GSH cycle.These processes stabilize reactive oxygen species level,alleviate lipid peroxidation degree,and decrease membrane permeability to further protect the intactness structure in mesophyll cell and chloroplast of S.viminalis exposed to Cd.关键词
褪黑素/镉/蒿柳/抗氧化系统Key words
melatonin/cadmium/Salix viminalis/antioxidant system分类
农业科技引用本文复制引用
殷佳慧,宁崴,李奥,李霞,刘俊祥,孙振元..褪黑素对镉胁迫下蒿柳抗氧化系统及叶肉细胞超微结构的影响[J].西北林学院学报,2024,39(4):1-14,14.基金项目
吉林省自然科学基金(联合基金项目)资助项目"基于镉污染植物修复的长白山区蒿柳资源评价及研究"(YDZJ202101ZYTS113). （联合基金项目）
