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Journal of Integrative Agriculture  2024, Vol. 23 Issue (7): 2270-2291    DOI: 10.1016/j.jia.2023.12.012
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Melatonin and dopamine alleviate waterlogging stress in apples by recruiting beneficial endophytes to enhance physiological resilience
Yang Cao*, Peihua Du*, Yuwei Shang, Jiahao Ji, Leiqing Tan, Xue Zhang, Jizhong Xu, Bowen Liang#

College of Horticulture, Hebei Agricultural University, Baoding 071001, China

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摘要  

褪黑素和多巴胺具有抵抗涝害胁迫的潜力。本研究旨在探讨褪黑素和多巴胺减轻苹果涝害胁迫的作用机制。本研究证明褪黑素和多巴胺通过清除活性氧(ROS)缓解涝害,且发现一氧化氮(NO)含量与硝酸还原酶(NR)活性显著相关。并且我们发现褪黑素和多巴胺招募了不同的潜在有益内生菌(褪黑素: Novosphingobium, Propionivibrio, Cellvibrio; 多巴胺: Hydrogenophaga, Simplicispira, Methyloversatilis, Candidatus_Kaiserbacteria,  Humicola),这些内生菌的相对丰度与植物生长呈显著正相关。网络分析表明,褪黑素和多巴胺显著影响涝害胁迫下的内生细菌和真菌群落。代谢组结果表明,褪黑素和多巴胺通过上调氨基酸、类黄酮、香豆素和有机酸等有益物质的丰度来抵抗涝害。此外,对土壤理化性质的研究发现,褪黑素和多巴胺对土壤理化性质具有调节作用,从而改变了土壤内生菌的群落结构,影响了植物的生长。共生网络揭示了内生菌、代谢产物、土壤和植物之间密切而复杂的关系。我们的研究结果表明,褪黑素和多巴胺通过招募有益的内生菌来增强苹果的生理适应性,从而减轻涝害胁迫。本研究为探明褪黑素和多巴胺减轻涝害胁迫的机制提供了新的见解,并为协同有益微生物抵抗涝害胁迫提供了理论基础。



Abstract  
Melatonin and dopamine can potentially prevent waterlogging stress in apples.  The current study investigated the mechanism by which melatonin and dopamine alleviate apple waterlogging stress.  This study demonstrated that melatonin and dopamine alleviated waterlogging by removing reactive oxygen species (ROS), and that the nitric oxide (NO) content and nitrate reductase (NR) activity were significantly correlated.  Melatonin and dopamine were also found to recruit different candidate beneficial endophytes (melatonin: Novosphingobium, Propionivibrio, and Cellvibrio; dopamine: Hydrogenophaga, Simplicispira, Methyloversatilis, Candidatus_Kaiserbacteria, and Humicola), and these endophytes were significantly and positively correlated with plant growth.  Network analyses showed that melatonin and dopamine significantly affected the endophytic bacterial and fungal communities under waterlogging stress.  The metabolomic results showed that melatonin and dopamine led to waterlogging resistance by upregulating the abundance of beneficial substances such as amino acids, flavonoids, coumarins, and organic acids.  In addition, melatonin and dopamine regulated the physicochemical properties of the soil, which altered the endophyte community and affected plant growth.  The co-occurrence network demonstrated close and complex relationships among endophytes, metabolites, soil, and the plants.  Our results demonstrate that melatonin and dopamine alleviate waterlogging stress in apples by recruiting beneficial endophytes to enhance physiological resilience.  This study provides new insights into how melatonin and dopamine alleviate stress and a theoretical basis for synergistic beneficial microbial resistance to waterlogging stress.


Keywords:  dopamine        endophytes        Malus hupehensis        melatonin        metabolomics        waterlogging  
Received: 16 June 2023   Accepted: 20 November 2023
Fund: 
This work was supported by the National Natural Science Foundation of China (31901964), the Natural Science Foundation of Hebei, China (C2021204158), the Science and Technology Project of Hebei Education Department, China (BJK2022012), the Introduced Talents Project of Hebei Agricultural University, China (YJ201904), the earmarked fund for Hebei Apple Innovation Team of Modern Agroindustry Technology Research System, China (HBCT2024150205) and the earmarked fund for the China Agricultural Research System, China (CARS-27).
About author:  #Correspondence Bowen Liang, E-mail: lbwnwsuaf@126.com, lbw@hebau.edu.cn *These authors contributed equally to this study.

Cite this article: 

Yang Cao, Peihua Du, Yuwei Shang, Jiahao Ji, Leiqing Tan, Xue Zhang, Jizhong Xu, Bowen Liang. 2024. Melatonin and dopamine alleviate waterlogging stress in apples by recruiting beneficial endophytes to enhance physiological resilience. Journal of Integrative Agriculture, 23(7): 2270-2291.

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