基于代谢组揭示蒴腐病对芝麻蒴果成分的影响

Metabolomics reveals the effects of capsule rot on the metabolites of sesame capsules

摘要:

【背景】 作为一种重要的油料作物，芝麻(Sesamum indicum L.)受到链格孢菌(Alternaria alternata)的侵染后会导致其产量降低，进而影响粮食安全和质量。【目的】 研究链格孢菌侵染芝麻蒴果后的差异代谢物及通路，以期了解该病害对芝麻蒴果的影响。【方法】 基于非靶向代谢组学技术，结合多元统计分析方法，分析链格孢菌侵染芝麻蒴果后的代谢物差异及代谢途径变化。【结果】 代谢组结果显示，在果皮和籽粒中一共注释到247种代谢物，分为11类。相较于对照组，链格孢菌侵染导致果皮和籽粒中的代谢物分别有126和231个上调，27和118个下调。差异代谢物的KEGG富集分析表明链格孢菌侵染影响到芝麻果皮和籽粒的氨基酸代谢、糖代谢、核苷酸代谢，从而影响到芝麻的食品质量。【结论】 链格孢菌侵染芝麻蒴果后，主要通过影响芝麻蒴果的果皮和籽粒的氨基酸代谢和糖代谢来影响芝麻的品质，为病害的发生提供了思路。

关键词:芝麻;链格孢菌;气相色谱法-质谱法联用

Abstract:

[Background] Sesame (Sesamum indicum L.) is an important oilseed crop susceptible to the infection by Alternaria alternata, which reduces the yield and subsequently impacts the security and quality of sesame. [Objective] This study investigated the differential metabolites and pathways in the sesame capsules infected by A.alternata, aiming to unveil the effects of this disease on sesame capsules. [Methods] Non-targeted metabolomics and multivariate statistical analysis were employed to analyze the metabolite differences and metabolic pathway changes in sesame capsules after infection by A. alternata. [Results] The metabolomic analysis revealed a total of 247 differential metabolites categorized into 11 classes in the capsule peel and seeds. Compared with the control group, A.alternata infection led to the up-regulation of 126 and 231 metabolites and down-regulation of 27 and 118 metabolites in the peel and seeds, respectively. The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of the differential metabolites indicated that A.alternata infection significantly affected the amino acid, carbohydrate, and nucleotide metabolism in the peel and seeds, thereby impacting sesame quality. [Conclusion] A.alternata infection affects the quality of sesame by influencing amino acid and carbohydrate metabolism in the capsule peel and seeds. This study provides clues for revealing the disease mechanism and managing this pathogen, thereby contributing to agricultural sustainability.

Key words:Sesamum indicum L.;Alternaria alternata;gas chromatography-mass spectrometry