School of Pharmacy, Hubei University of Chinese Medicine, 430065, Wuhan, China; Hubei Shizhen Laboratory, Hubei University of Chinese Medicine, 430065, Wuhan, China.
School of Pharmacy, Hubei University of Chinese Medicine, 430065, Wuhan, China; Hubei Shizhen Laboratory, Hubei University of Chinese Medicine, 430065, Wuhan, China.
Plant Physiol Biochem. 2024 Dec;217:109296. doi: 10.1016/j.plaphy.2024.109296. Epub 2024 Nov 14.
Verticillium wilt, a significant pathogen affecting cotton, has historically been challenging to control, posing a substantial threat to the sustainable development of the cotton industry. This study demonstrates that resistance to Verticillium dahliae in cotton can be enhanced by treating the roots with an ethyl acetate extract (EAAA) extracted from Artemisia argyi. The mechanisms by which EAAA activates immunity in cotton were elucidated by examining the expression levels of resistance genes post-treatment, evaluating salicylic acid (SA) and jasmonic acid (JA) levels, analyzing transcriptome data, and employing virus-induced gene silencing (VIGS) technology. Additionally, pot experiments were conducted to validate the efficacy of EAAA in controlling Verticillium wilt. The flavonoid content in EAAA was qualitatively analyzed using Ultra-Performance Liquid Chromatography coupled with Tandem Mass Spectrometry (UPLC-MS/MS), identifying three specific flavonoids that were further screened to verify their roles in activating cotton immunity. Cotton plants treated with EAAA exhibited reduced leaf chlorosis and browning in the vascular bundles. Genes involved in SA and JA synthesis and signaling in the root system were highly expressed, resulting in increased levels of SA and JA. Transcriptome analysis revealed that most upregulated differentially expressed genes were primarily enriched in the Mitogen-Activated Protein Kinase (MAPK) signaling pathway. Two specific genes, RLK and MAPKKK18, were identified through VIGS technology as key regulators of the immune pathway in cotton. The flavonoid monomer activation experiment demonstrated that eupatilin, hispidulin, jaceosidin, and a mixture of these three could induce the expression of cotton-related resistance genes. Collectively, these findings provide a research basis for the development of EAAA as a natural plant immune-inducing agent against cotton Verticillium wilt.
黄萎病是一种严重影响棉花的病原体，历史上难以控制，对棉花产业的可持续发展构成了重大威胁。本研究表明，用艾草乙酸乙酯提取物（EAAA）处理棉花根部可以增强棉花对黄萎病的抗性。通过检测处理后抗性基因的表达水平、评估水杨酸（SA）和茉莉酸（JA）水平、分析转录组数据以及采用病毒诱导的基因沉默（VIGS）技术，阐明了 EAAA 激活棉花免疫的机制。此外，还进行了盆栽实验以验证 EAAA 控制黄萎病的功效。采用超高效液相色谱-串联质谱联用技术（UPLC-MS/MS）对 EAAA 中的类黄酮含量进行定性分析，鉴定出三种特定的类黄酮，并进一步筛选以验证它们在激活棉花免疫中的作用。用 EAAA 处理的棉花植株叶片叶脉的褪绿和黄化现象减轻。根系中与 SA 和 JA 合成和信号转导相关的基因高度表达，导致 SA 和 JA 水平升高。转录组分析表明，大多数上调的差异表达基因主要富集在丝裂原活化蛋白激酶（MAPK）信号通路中。通过 VIGS 技术鉴定出两个特定基因，即 RLK 和 MAPKKK18，它们是棉花免疫途径的关键调控因子。类黄酮单体激活实验表明，野马追乙素、羟基吴茱萸碱、木犀草素苷和它们的混合物均可诱导棉花相关抗性基因的表达。综上所述，这些发现为开发 EAAA 作为防治棉花黄萎病的天然植物免疫诱导剂提供了研究基础。
