外源-5氨基乙酰丙酸对干旱胁迫下紫花苜蓿生理特性及次生代谢物含量的影响  

Effect of Exogenous 5-Aminolevulinic Acid on Physiological Characteristics and Secondary Metabolite Contents of Alfalfa Seedling under Drought Stress

作　　者：李丹丹[1] 梁宗锁[2] 杨宗岐[2] 徐学选[1] 韩蕊莲[1,3] LI Dandan;LIANG Zongsuo;YANG Zongqi;XU Xuexuan;HAN Ruilian(College of Grassland Agriculture,Northwest A&F University,Yangling,Shaanxi 712100,China;School of Life Science and Medicine,Zhejiang Sci-Tech University,Hangzhou 310018,China;School of Civil Engineering and Architecture,Zhejiang Sci-Tech University,Hangzhou 310018,China)

机构地区：[1]西北农林科技大学草业与草原学院,陕西杨陵712100 [2]浙江理工大学生命科学与医药学院,杭州310018 [3]浙江理工大学建筑工程学院,杭州310018

出　　处：《西北植物学报》2019年第10期1827-1834,共8页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金(No.31570370);国家科技支撑项目(2015BAC01B03)

摘　　要：为验证喷施不同浓度5-氨基乙酰丙酸(ALA)对紫花苜蓿的响应,该研究以紫花苜蓿品种‘农牧806’为实验材料,用不同浓度(0、5、10、15、20、25 mg·L^-1)的ALA喷施处理15%聚乙二醇(PEG-6000)模拟干旱胁迫下的紫花苜蓿幼苗,并测定其相关的生理生化指标以及次生代谢物质积累量。结果表明:(1)与对照相比,15%PEG干旱胁迫使得紫花苜蓿叶片中光合色素含量降低,渗透调节物质含量以及抗氧化酶活性增高。(2)与15%PEG处理相比,ALA+15%PEG复配处理下紫花苜蓿幼苗叶片叶绿素a、b和类胡萝卜素以及叶绿素总量分别增加,抗氧化酶(CAT, POD, SOD)活性升高,可溶性蛋白和脯氨酸以及黄酮和皂苷含量上升,丙二醛、H2O2和·OH的含量降低,各浓度ALA对15%PEG不同时长胁迫的恢复效果不同。研究发现,叶面喷施适量浓度ALA能够有效提高干旱胁迫下紫花苜蓿叶片抗氧化酶活性以及渗透调节物质、次生代谢物(黄酮、皂苷)含量和光合色素含量,从而增强紫花苜蓿对干旱胁迫的耐受性,并以10 mg·L^-1ALA的缓解效果较显著。To verify the response of different concentrations of 5-aminolevulinic acid(ALA), we sprayed alfalfa(cv. Nongmu 806) seedlings with 15% PEG-6000 and ALA with different concentrations(0, 5, 10, 15, 20, 25 mg·L^-1), and 1/2 Hogland nutrient solution was used as control. Then, the physiological, biochemical indexes and secondary metabolite of ’Nongmu 806’ seedlings were determined. Results revealed that:(1) compared with the control, 15% PEG simulated drought stress reduced the contents of chlorophyll a, b, carotenoid and chlorophyll in alfalfa leaves, increased the content of osmotic adjustment substances and the activities of antioxidant enzymes.(2) After ALA and 15% PEG treatment, the contents of chlorophyll a, b, carotenoid and chlorophyll of alfalfa seedling leaves increased, the activities of CAT, POD, SOD and the contents of soluble protein, proline, flavonoids and saponins increased, whereas the contents of malondialdehyde, H2O2 and·OH decreased compared with 15% PEG treatment. The results showed that spraying ALA can effectively improve the tolerance of alfalfa to drought stress. However, different concentrations of ALA have different recovery effects on 15% PEG, and 10 mg·L^-1 ALA had the most significant effect.

关 键 词：外源5-氨基乙酰丙酸(ALA) 紫花苜蓿 干旱胁迫 抗氧化酶 渗透调节物质 次生代谢物质 

分 类 号：Q945.78[生物学—植物学]