Institute of Biological, Environmental and Rural Science, Aberystwyth University, Aberystwyth, Wales, UK.
Software College, Shanxi Agricultural University, Taigu, Shanxi, China.
Physiol Plant. 2022 Jan;174(1):e13597. doi: 10.1111/ppl.13597. Epub 2021 Dec 22.
Drought is a major abiotic stress that limits crop productivity and is driving the need to introduce new tolerant crops with better economic yield. Tef (Eragrostis tef) is a neglected (orphan) Ethiopian warm-season annual gluten-free cereal with high nutritional and health benefits. Further, tef is resilient to environmental challenges such as drought, but the adaptive mechanisms remain poorly understood. In this study, metabolic changes associated with drought response in 11 tef accessions were identified using phenomic and metabolomic approaches under controlled conditions. Computerized image analysis of droughted plants indicated reductions in leaf area and green pigments compared with controls. Metabolite profiling based on flow-infusion electrospray-high-resolution mass spectroscopy (FIE-HRMS) showed drought associated changes in flavonoid, phenylpropanoid biosynthesis, sugar metabolism, valine, leucine and isoleucine biosynthesis, and pentose phosphate pathways. Flavonoid associated metabolites and TCA intermediates were lower in the drought group, whereas most of the stress-responsive amino acids and sugars were elevated. Interestingly, after drought treatment, one accession Enatite (Ent) exhibited a significantly higher plant area than the others, and greater accumulation of flavonoids, amino acids (serine and glycine), sugars (ribose, myo-inositol), and fatty acids. The increased accumulation of these metabolites could explain the increased tolerance to drought in Ent compared with other accessions. This is the first time a non-targeted metabolomics approach has been applied in tef, and our results provide a framework for a better understanding of the tef metabolome during drought stress that will help to identify traits to improve this understudied potential crop.
干旱是一种主要的非生物胁迫，限制了作物的生产力，并促使人们需要引入具有更好经济产量的新的耐受作物。埃塞俄比亚的画眉草（Eragrostis tef）是一种被忽视（孤儿）的温暖季节一年生无麸质谷物，具有很高的营养价值和健康益处。此外，画眉草能抵抗干旱等环境挑战，但适应机制仍知之甚少。在这项研究中，我们采用表型和代谢组学方法，在受控条件下，鉴定了 11 个画眉草品种对干旱响应相关的代谢变化。与对照相比，对干旱植株的计算机图像分析表明，叶片面积和绿色素减少。基于流动进样电喷雾-高分辨质谱（FIE-HRMS）的代谢物分析表明，干旱导致类黄酮、苯丙烷生物合成、糖代谢、缬氨酸、亮氨酸和异亮氨酸生物合成以及戊糖磷酸途径发生变化。在干旱组中，类黄酮相关代谢物和 TCA 中间产物减少，而大多数应激响应的氨基酸和糖增加。有趣的是，在干旱处理后，一个品种 Enatite（Ent）的植物面积明显高于其他品种，类黄酮、氨基酸（丝氨酸和甘氨酸）、糖（核糖、肌醇）和脂肪酸的积累也更高。这些代谢物的增加积累可以解释 Ent 比其他品种对干旱的耐受性更高。这是首次在画眉草中应用非靶向代谢组学方法，我们的研究结果为更好地理解画眉草在干旱胁迫下的代谢组提供了一个框架，有助于鉴定提高这种研究较少的潜在作物的特性。
