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草业学报 ›› 2024, Vol. 33 ›› Issue (10): 135-146.DOI: 10.11686/cyxb2023426

• 研究论文 • 上一篇    

外源褪黑素介导抗氧化和苯丙烷代谢提高燕麦叶斑病抗性的研究

王正(), 李新, 张建贵, 柴继宽, 赵桂琴, 牛奎举()   

  1. 甘肃农业大学草业学院,草业生态系统教育部重点实验室,甘肃 兰州 730070
  • 收稿日期:2023-11-14 修回日期:2024-01-18 出版日期:2024-10-20 发布日期:2024-07-15
  • 通讯作者: 牛奎举
  • 作者简介:Corresponding author. E-mail: niukj@gsau.edu.cn
    王正(1999-),男,内蒙古巴彦淖尔人,在读硕士。E-mail: 1192597943@qq.com
  • 基金资助:
    财政部和农业农村部国家现代农业产业技术体系(CARS-07-C-1);山丹县半干旱区饲用燕麦一年两季栽培加工技术研究项目(GSAU-JSYF-2023-16);燕麦育种项目(NK2022140202-1)

Exogenous melatonin mediates the antioxidant system and phenylpropanoid metabolism to induce resistance to leaf spot disease in oat

Zheng WANG(), Xin LI, Jian-gui ZHANG, Ji-kuan CHAI, Gui-qin ZHAO, Kui-ju NIU()   

  1. College of Pratacultural Science,Gansu Agricultural University,Key Laboratory of Grassland Ecosystem,Ministry of Education,Lanzhou 730070,China
  • Received:2023-11-14 Revised:2024-01-18 Online:2024-10-20 Published:2024-07-15
  • Contact: Kui-ju NIU

摘要:

为探究外源褪黑素对燕麦抗叶斑病的诱导效应及诱导抗病机理,本研究以‘牧乐思’燕麦品种为试验材料,叶面喷施不同浓度褪黑素(0、10、100、250、500和1000 μmol·L-1)后接种燕麦徳氏霉病原菌,以未接种病原菌为对照,接种病原菌9 d后统计病情指数和采集叶片测定抗氧化系统、苯丙烷代谢相关生理指标和相关酶基因相对表达量。结果表明,叶斑病明显抑制燕麦生长,喷施不同浓度褪黑素后叶斑病病情指数明显降低,其中100 μmol·L-1褪黑素处理下病原菌体外诱导效率、过氧化氢酶、苯丙氨酸解氨酶活性和抗坏血酸过氧化物酶基因表达量最高,分别高于只接种病原菌处理50.72%、80.32%、3.88%和148.00%;250 μmol·L-1褪黑素处理下超氧阴离子产生速率和丙二醛含量最低,分别低于只接种病原菌处理28.27%和86.62%,超氧化物歧化酶、过氧化物酶、抗坏血酸过氧化物酶、肉桂酸-4-羟化酶、4-香豆酸∶辅酶A连接酶活性、木质素、总酚、类黄酮含量和超氧化物歧化酶、过氧化物酶、过氧化氢酶、苯丙氨酸解氨酶、4-香豆酸∶辅酶A连接酶、肉桂酸-4-羟化酶基因表达量最高,分别高于只接种病原菌处理128.23%、137.14%、74.00%、52.65%、26.73%、1.40%、10.33%、13.70%、352.56%、80.32%、65.71%、26.65%、52.65%和20.11%;500 μmol·L-1褪黑素处理下过氧化氢含量最低,低于只接种病原菌处理75.45%,叶绿素含量最高,高于只接种病原菌处理81.35%。综合各项指标结果,筛选出最适诱导浓度为250 μmol·L-1,试验结果可为燕麦防治叶斑病提供新途径。

关键词: 燕麦, 褪黑素, 诱导抗病性, 叶斑病

Abstract:

The aim of this work was to determine how exogenous melatonin affects the resistance of oat (Avena sativa) to leaf spot disease caused by the pathogen Drechslera avenae. Seedlings of the oat cultivar ‘Molasses’ were subjected to foliar spraying with melatonin (0, 10, 100, 250, 500, and 1000 μmol·L-1) followed by inoculation with the pathogen. At 9 days after inoculation, the disease index was calculated, and physiological indicators and the transcript levels of genes related to the antioxidant system and phenylpropanoid metabolism were determined. The results showed that leaf spot disease significantly inhibited oat plant growth, but the disease index was significantly decreased when melatonin was applied. The degree to which the disease index was decreased differed depending on the melatonin concentration. The in vitro induction efficiency of the pathogen, the activities of catalase and phenylalanine ammonia lyase, and the transcript level of the gene encoding ascorbate peroxidase were highest in the 100 μmol·L-1 melatonin treatment, and were 50.72%, 80.32%, 3.88%, and 148.00% higher than their respective values in the control. The lowest superoxide anion production rate and malondialdehyde content were in the 250 μmol·L-1 melatonin treatment, and were 28.27% and 86.62% lower than their respective values in the control. Compared with the control, in the 250 μmol·L-1 melatonin treatment, the activities of superoxide dismutase, peroxidase, ascorbate peroxidase, cinnamic acid-4-hydroxylase, and 4-coumaric acid∶CoA ligase were increased by 128.23%, 137.14%, 74.00%, 52.65%, and 26.73%, respectively; the contents of lignin, total phenols, and flavonoids were increased by 1.40%, 10.33%, and 13.70%, respectively, and the transcript levels of genes encoding superoxide dismutase, peroxidase, catalase, phenylalanine ammonia lyase, 4-coumaric acid∶CoA ligase, and cinnamic acid-4-hydroxylase were increased by 352.56%, 80.32%, 65.71%, 26.65%, 52.65%, and 20.11%, respectively. Seedlings treated with 500 μmol·L-1 melatonin showed the lowest hydrogen peroxide content (75.45% lower than that in the control) and the highest chlorophyll content (81.35% higher than that in the control). According to the above results, the best concentration of melatonin for inducing resistance to leaf spot in oat plants is 250 μmol·L-1. The results of this study demonstrate a new approach for the control of leaf spot disease in oat.

Key words: oat, melatonin, induced disease resistance, leaf spot