Soil waterlogging and high-temperature events have occurred simultaneously in recent years in the Yangtze River basin cotton belt region of China, negatively affecting the development and quality of cottonseed. This study investigated the effects of the combination of elevated temperature (34.1/29.0°C) and waterlogging (3 or 6 days) on the accumulation and distribution of oil, protein and carbohydrates in cottonseed during flowering and boll development. The results showed that elevated temperature (ET) resulted in greater decreases in cottonseed biomass under waterlogging than under control conditions. The combination of waterlogging and ET significantly limited the accumulation of carbohydrates and oil contents. However, ET promoted protein accumulation and compensated for the negative effects of 3-day waterlogging on the final protein content. The combined ET and 6-day waterlogging significantly decreased the final contents of oil and protein by limiting carbon flux and NADPH supply due to the decreased activities of Phosphoenolpyruvate Carboxylase (PEPC, EC 4.1.1.31) and Glucose-6-Phosphate Dehydrogenase (G6PDH, EC 1.1.1.49). The PEPC activity was correlated more with protein content than oil content. In addition, simultaneous exposure to waterlogging and ET resulted in lower unsaturated fatty acid (UFA)/saturated fatty acid (SFA) ratios and essential amino acid (EAA)/non-essential amino acid (NAA) ratios than did exposure to the individual factors alone. These findings could provide the theoretical support for the prospective assessment of effects of high temperature and waterlogging stresses on cotton production under climate change, and they can help to develop effective techniques in cotton cultivation. This article is protected by copyright. All rights reserved.

中文翻译：

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高温和涝渍通过改变碳水化合物、油和蛋白质的积累和分布来降低棉花种子质量

近年来，我国长江流域棉带地区土壤涝渍和高温事件同时发生，严重影响了棉籽的发育和品质。本研究调查了高温（34.1/29.0°C）和涝渍（3 或 6 天）的组合对开花和棉铃发育过程中棉籽中油、蛋白质和碳水化合物的积累和分布的影响。结果表明，与对照条件相比，高温（ET）导致涝渍条件下棉籽生物量的下降幅度更大。涝渍和ET的结合显着限制了碳水化合物和油含量的积累。然而，ET 促进了蛋白质的积累，并弥补了 3 天涝渍对最终蛋白质含量的负面影响。由于磷酸烯醇丙酮酸羧化酶 (PEPC, EC 4.1.1.31) 和葡萄糖-6-磷酸脱氢酶 (G6PDH,欧共体 1.1.1.49)。PEPC 活性与蛋白质含量的相关性比与油含量的相关性更大。此外，与暴露于单个因素相比，同时暴露于涝渍和 ET 导致不饱和脂肪酸 (UFA)/饱和脂肪酸 (SFA) 比率和必需氨基酸 (EAA)/非必需氨基酸 (NAA) 比率降低独自的。这些发现可为气候变化下高温和涝渍胁迫对棉花生产的影响的前瞻性评估提供理论支持，他们可以帮助开发有效的棉花种植技术。本文受版权保护。版权所有。