SA对低温胁迫后枇杷幼果AsA-GSH循环酶系统的影响  

Effects of SA on Enzymes of Ascorbate-glutathione Cycle in Young Loquat Fruits after Low Temperature Stress

作　　者：黄志明[1] 吴锦程[1] 陈伟健[1] 蔡丽琴[1] 谢翠萍[1] 林良津[1] 黄世杰[1] 叶美兰[1] 

机构地区：[1]莆田学院环境与生命科学系,莆田351100

出　　处：《林业科学》2011年第9期36-42,共7页Scientia Silvae Sinicae

基　　金：福建省科技计划重点项目(2007I0021);福建省自然科学基金项目(2008J0071);莆田市科技计划重点项目(2007N26);福建省高校服务海西重点建设项目(2008HX02)

摘　　要：研究水杨酸处理对"早钟6号"枇杷幼果AsA-GSH循环酶系统的影响,探讨SA对枇杷幼果抗寒性的作用机理。结果表明:采用40和70mg·L-1的SA处理可提高低温胁迫后枇杷幼果还原型谷胱甘肽(GSH)含量,降低氧化型谷胱甘肽(GSSG)含量,导致GSH/GSSG比率的上升,同时也提高低温胁迫后枇杷幼果谷胱甘肽还原酶(GR)、谷胱甘肽过氧化物酶(GPX)和谷胱甘肽-S-转移酶(GST)的活性,启动细胞的解毒功能,从而降解低温胁迫后所产生的过量过氧化产物。此外,SA处理还可提高低温胁迫后枇杷幼果抗坏血酸过氧化物酶(APX)、脱氢抗坏血酸还原酶(DHAR)和单脱氢抗坏血酸还原酶(MDAR)活性以及还原型抗坏血酸(AsA)含量,降低氧化型抗坏血酸(DHA)、过氧化氢(H2O2)和丙二醛(MDA)含量以及相对电导率(REC),导致AsA/DHA比率的上升,提高枇杷幼果组织内部的抗氧化能力,从而起到保护作用。SA处理可提高低温胁迫后枇杷幼果的抗氧化性,增强其抗寒能力,其中以70mg·L-1的SA处理效果较好。A study on effects of salicylic acid（SA） treatment on enzymes of ascorbate-glutathione cycle in young loquat（Eriobotrya japonica cv.＇Zaozhong No.6＇） fruits was conducted to explore the mechanism of SA in promoting the chill-resistance of young loquat fruits to low temperature.Results indicated that 40 and 70 mg·L-1 SA treatments increased the reduced glutathione（GSH） contents,and decreased the oxidized glutathione（GSSG） content.Therefore,the treatment resulted in elevating the ratio of GSH/GSSG in young loquat fruits under low temperature stress.Meanwhile,SA treatment also promoted the activities of GSH-dependent glutathione reductase（GR）,glutathione-S-transferases（GST）,and glutathione peroxidase（GPX） in young loquat fruits,which could activate its cell detoxification function by degrading peroxides caused by low temperature stress.Furthermore,SA treatment increased ascorbate peroxidase（APX）,dehydroascorbate reductase（DHAR）,monodehydroascorbate reductase（MDAR） activities and ascorbate（AsA） contents,and decreased the contents of dehydroascorbate（DHA）,super hydrogen（H2O2）,malondialdehyde（MDA） contents and relative electric conductivity（REC）,which led to an increase of AsA/DHA ratio,and ultimately resulted in alleviating the oxidative damage caused by low temperature stress.It is concluded that SA could significantly improve oxidation resistance and chill-resistance of young loquat fruits.SA concentration at 70 mg·L-1 was preferable for young loquat fruits.

关 键 词：枇杷幼果 水杨酸 低温胁迫 AsA-GSH循环 

分 类 号：Q948.1[生物学—植物学]