Hamany Djande Claude Y, Piater Lizelle A, Steenkamp Paul A, Tugizimana Fidele, Dubery Ian A
Research Centre for Plant Metabolomics, Department of Biochemistry, University of Johannesburg, P.O. Box 524, Auckland Park, Johannesburg 2006, South Africa.
Metabolites. 2021 Aug 26;11(9):578. doi: 10.3390/metabo11090578.
One of the ultimate goals of plant breeding is the development of new crop cultivars capable of withstanding increasing environmental stresses, to sustain the constantly growing population and economic demands. Investigating the chemical composition of the above and underground tissues of cultivars is crucial for the understanding of common and specific traits thereof. Using an untargeted metabolomics approach together with appropriate chemometrics tools, the differential metabolite profiles of leaf and root extracts from five cultivars of barley ('Erica', 'Elim', 'Hessekwa', 'S16' and 'Agulhas') were explored and potential signatory biomarkers were revealed. The study was conducted on seedlings grown for 21 days under identical controlled conditions. An ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS) was employed to analyse hydromethanolic leaf and root extracts of barley cultivars. Furthermore, unsupervised and supervised learning algorithms were applied to mine the generated data and to pinpoint cultivar-specific metabolites. Among all the classes of metabolites annotated, phenolic acids and derivatives formed the largest group and also represented the most discriminatory metabolites. In roots, saponarin, an important allelochemical differentially distributed across cultivars, was the only flavonoid annotated. The application of an untargeted metabolomics approach in phenotyping grain crops such as barley was demonstrated, and the metabolites responsible for differentiating between the selected cultivars were revealed. The study provides insights into the chemical architecture of barley, an agro-economically relevant cereal crop; and reiterates the importance of metabolomics tools in plant breeding practices for crop improvement.
植物育种的最终目标之一是培育出能够抵御日益增加的环境压力的新作物品种，以满足不断增长的人口和经济需求。研究品种地上和地下组织的化学成分对于了解其共性和特性至关重要。采用非靶向代谢组学方法并结合适当的化学计量学工具，探索了五个大麦品种（“埃丽卡”、“埃利姆”、“赫塞夸”、“S16”和“阿古拉斯”）叶片和根系提取物的差异代谢物谱，并揭示了潜在的标志性生物标志物。该研究在相同控制条件下培养21天的幼苗上进行。采用超高效液相色谱-高分辨质谱联用技术（UHPLC-HRMS）分析大麦品种的叶和根的氢甲醇提取物。此外，应用无监督和有监督学习算法挖掘生成的数据，以确定品种特异性代谢物。在所有注释的代谢物类别中，酚酸及其衍生物构成了最大的组，也是最具区分性的代谢物。在根系中，皂草苷是唯一注释的黄酮类化合物，它是一种重要的化感物质，在不同品种间差异分布。证明了非靶向代谢组学方法在大麦等谷类作物表型分析中的应用，并揭示了区分所选品种的代谢物。该研究为大麦这一具有农业经济价值的谷类作物的化学结构提供了见解；并重申了代谢组学工具在作物改良的植物育种实践中的重要性。
