Table_5_Assessment of the changes in seed yield and nutritional quality of quinoa grown under rainfed Mediterranean environments.docx

Climate change is considered a serious threat to agriculture and food security. It is linked to rising temperatures and water shortages, conditions that are expected to worsen in the coming decades. Consequently, the introduction of more drought-tolerant crops is required. Quinoa (Chenopodium quinoa Willd.) has received great attention worldwide due to the nutritional properties of its seeds and its tolerance to abiotic stress. In this work, the agronomic performance and seed nutritional quality of three quinoa varieties were studied during two consecutive years (2019-2020) under three water environmental conditions of Southwestern Europe (irrigated conditions, fresh rainfed, and hard rainfed) with the goal of determining the impact of rainfed conditions on this crop performance. High precipitations were recorded during the 2020 growing season resulting in similar grain yield under irrigation and fresh rainfed conditions. However, in 2019, significant yield differences with penalties under water-limiting conditions were found among the evaluated environmental conditions. Furthermore, nutritional and metabolomic differences were observed among seeds harvested from different water environments including the progressive accumulation of glycine betaine accompanied by an increase in saponin and a decrease in iron with water limitation. Generally, water-limiting environments were associated with increased protein contents and decreased yields preserving a high nutritional quality despite particular changes. Overall, this work contributes to gaining further knowledge about how water availability affects quinoa field performance, as it might impact both seed yield and quality. It also can help reevaluate rainfed agriculture, as water deficit can positively impact the nutritional quality of seeds.

气候变化被视为对农业与粮食安全的严峻威胁。其与气温升高、水资源短缺密切相关，且这类状况预计在未来数十年内将持续恶化。因此，培育更多耐旱作物成为迫切需求。
藜麦（Quinoa，学名*Chenopodium quinoa Willd.*）因籽粒富含营养且耐非生物胁迫（abiotic stress），已在全球范围内受到广泛关注。本研究于2019至2020年连续两个生长季内，在欧洲西南部三种不同水分环境条件下（灌溉条件、轻度雨养条件与重度雨养条件），对三个藜麦品种的农艺性状表现及籽粒营养品质展开分析，旨在明确雨养农业（rainfed agriculture）条件对该作物生长表现的影响。
2020年生长季降雨量偏高，使得灌溉条件与轻度雨养条件下的籽粒产量无显著差异。但在2019年，各供试环境条件下，水分限制环境均导致产量显著下降，且不同环境间存在显著产量差异。此外，不同水分环境下收获的藜麦籽粒在营养成分与代谢组学（metabolomic）特征上均存在差异：随着水分限制程度加深，甘氨酸甜菜碱（glycine betaine）的积累量逐渐升高，皂苷（saponin）含量增加，而铁元素含量则有所下降。
总体而言，水分限制环境下藜麦的蛋白质含量有所提升，但籽粒产量下降；尽管存在上述特定变化，其仍能保持较高的营养品质。综上，本研究进一步阐明了水分供应如何影响藜麦的田间生长表现——这一因素同时会对籽粒产量与品质产生影响。同时，本研究有助于重新评估雨养农业的价值，因为水分亏缺可对籽粒营养品质产生积极影响。