褪黑素和海藻酸对高温胁迫下高山杜鹃抗氧化酶系统的影响  

Effects of melatonin and alginic acid on antioxidant enzyme sys⁃tem of Rhododendron lapponicum under high temperature stress

作　　者：陈睿[1] 鲜小林[1] CHEN Rui;XIAN Xiao-lin(Horticulture Research Institute,Sichuan Academy of Agricultural Sciences/Key Laboratory of Horticultural Crops Biology and Germplasm Enhancement in Southwest Regions,Ministry of Agriculture and Rural Affairs,Chengdu,Sichuan 610066,China)

机构地区：[1]四川省农业科学院园艺研究所/农业农村部西南地区园艺作物生物学与种质创制重点实验室,四川成都610066

出　　处：《南方农业学报》2024年第10期2875-2885,共11页Journal of Southern Agriculture

基　　金：四川省育种攻关项目(2021YFYZ0006);四川省财政自主创新专项(2022ZZCX051)。

摘　　要：【目的】探究喷施外源褪黑素和海藻酸对高温胁迫下高山杜鹃抗氧化酶系统的影响,为高山杜鹃抗热剂研究提供方向。【方法】以不耐热高山杜鹃品种薰衣草王子为试验材料,分别经对照组(清水,CK)和浓度组(100、200、300μmol/L褪黑素与200、300、400 mg/L海藻酸)处理后进行高温胁迫(昼夜胁迫温度40℃/28℃),研究外源褪黑素和海藻酸对高温胁迫下高山杜鹃抗氧化酶活性和抗氧化物质含量的影响。【结果】随着高温胁迫的开始和持续,各处理高山杜鹃丙二醛(MDA)含量总体上呈增加趋势;超氧化物歧化酶(SOD)活性总体上呈先上升后下降再上升的变化趋势;过氧化物酶(POD)和过氧化氢酶(CAT)活性均呈先上升后下降的变化趋势;谷胱甘肽还原酶(GSH)含量呈先上升后下降的变化趋势。同时,随着高温胁迫的开始和持续,各处理质膜H^(+)-ATPase活性缓慢下降,质膜Ca^(2+)-ATPase活性呈先上升后下降的变化趋势。高温胁迫96 h,与同期CK相比,6个浓度组MDA含量显著低6.36%~33.68%(P<0.05,下同)、SOD活性显著高21.68%~73.96%、POD活性显著高12.92%~49.02%、CAT活性高1.25%~43.10%、GSH含量高7.70%~49.79%、质膜H^(+)-ATPase活性显著高11.61%~53.00%、质膜Ca^(2+)-ATPase活性显著高9.36%~50.89%。相关分析结果表明,除CAT活性与SOD活性无显著相关性外,其他各指标间均呈极显著相关(P<0.01)。【结论】叶面喷施适宜浓度的外源褪黑素和海藻酸均能降低高温胁迫下高山杜鹃的MDA含量,提高SOD、POD、CAT活性和GSH含量,同时增强质膜H^(+)-ATPase和Ca^(2+)-ATPase活性,缓解高温胁迫对高山杜鹃生长的不利影响。同期喷施外源褪黑素总体上各指标优于海藻酸,其中,以喷施100μmol/L褪黑素的综合效果最佳,200 mg/L海藻酸也有较好的效果。【Objective】The study aimed to explore the effects of spraying exogenous melatonin(MT)and alginic acid(AA)on the antioxidant enzyme system of Rhododendron lapponicum under high temperature stress,providing direction for research on heat-resistant agents for R.lapponicum.【Method】Using the heat-sensitive R.lapponicum variety Prince Lavender as the experimental material,the plants were subjected to treatments of a control group(water,CK)and concentration groups(MT at 100,200 and 300μmol/L and AA at 200,300 and 400 mg/L).Following the treatments,high temperature stress(day/night stress temperature was 40℃/28℃)was applied to study the effects of exogenous MT and AA on the antioxidant enzyme activity and antioxidant content of R.lapponicum under high temperature stress.【Result】Under high temperature stress,the content of malondialdehyde(MDA)of R.lapponicum in all treatments showed an overall increasing trend with the onset and duration of the stress.The activity of superoxide dismutase(SOD)initially increased,then decreased,and subsequently increased again.The activities of peroxidase(POD)and catalase(CAT)both exhibited a trend of first increasing and then decreasing,while the content of glutathione(GSH)also showed an initial increase followed by a decrease.Meanwhile,as high temperature stress began and continued,the activity of plasma membrane H^(+)-ATPase in all treatments gradually decreased,whereas the activity of plasma membrane Ca^(2+)-ATPase exhibited a trend of first increasing and then decreasing.After 96 h of high temperature stress,compared to the CK during the same period,the contents of MDA in the 6 concentration groups was significantly decreased by 6.36%-33.68%(P<0.05,the same below),while SOD activity was significantly increased by 21.68%-73.96%,POD activity was significantly increased by 12.92%-49.02%,CAT activity increased by 1.25%-43.10%,GSH content increased by 7.70%-49.79%,the activity of plasma membrane H^(+)-ATPase increased significantly by 11.61%-53.00%,and the activity of plasm

关 键 词：高山杜鹃 高温胁迫 褪黑素 海藻酸 抗氧化 

分 类 号：S685.20[农业科学—观赏园艺]