Amoah Joseph N, Adu-Gyamfi Monica Ode
School of Life and Environmental Sciences, University of Sydney, 380 Werombi Road, Brownlow Hill, Camden, NSW, 2570, Australia.
Plant Biotechnology Department, CSIR - Crop Research Institute, Kumasi, Ghana.
Protoplasma. 2025 Jan;262(1):35-49. doi: 10.1007/s00709-024-01976-5. Epub 2024 Aug 5.
Drought stress triggers sugar accumulation in plants, providing energy and aiding in protection against oxidative damage. Plant hardening under mild stress conditions has been shown to enhance plant resistance to severe stress conditions. While sugar accumulation and metabolism under drought stress have been well-documented in crop plants, the effect of drought acclimation treatment on sugar accumulation and metabolism has not yet been explored. In this study, we investigated the impact of drought stress acclimation on sugar accumulation and metabolism in the leaves and root tissues of two commonly cultivated foxtail millet (Setaria italica L.) genotypes, 'PI 689680' and 'PI 662292'. Quantification of total sugars (soluble sugar, fructose, glucose, and sucrose), their related enzymes (SPS, SuSy, NI, and AI), and the regulation of their related transcripts (SiSPS1, SiSuSy1, SiSWEET6, SiA-INV, and SiC-INV) revealed that drought-acclimated (DA) plants exhibited levels of these indicators comparable to those of control plants. However, under subsequent drought stress conditions, both the leaves and roots of non-acclimated plants accumulated higher levels of total sugars, displayed increased activity of sugar metabolism enzymes, and showed elevated expression of sugar metabolism-related transcripts compared to drought-acclimated plants. Thus, acclimation-induced restriction of sugar accumulation, transport, and metabolism could be one of the metabolic processes contributing to enhanced drought tolerance in millet. This study advocates for the use of acclimation as an effective strategy to mitigate the negative impacts of drought-induced metabolic disturbances in millet, thereby enhancing global food security and promoting sustainable agricultural systems.
干旱胁迫会引发植物体内糖分积累，为植物提供能量并帮助抵御氧化损伤。研究表明，在轻度胁迫条件下对植物进行锻炼可增强其对重度胁迫条件的抗性。虽然作物在干旱胁迫下的糖分积累和代谢已有充分记录，但干旱驯化处理对糖分积累和代谢的影响尚未得到研究。在本研究中，我们调查了干旱胁迫驯化对两种常见栽培谷子（Setaria italica L.）基因型‘PI 689680’和‘PI 662292’的叶片和根组织中糖分积累和代谢的影响。对总糖（可溶性糖、果糖、葡萄糖和蔗糖）、其相关酶（SPS、SuSy、NI和AI）及其相关转录本（SiSPS1、SiSuSy1、SiSWEET6、SiA-INV和SiC-INV）的定量分析表明，经过干旱驯化（DA）的植株这些指标的水平与对照植株相当。然而，在随后的干旱胁迫条件下，与经过干旱驯化的植株相比，未驯化植株的叶片和根中总糖积累水平更高，糖代谢酶活性增加，糖代谢相关转录本的表达也升高。因此，驯化诱导的糖分积累、运输和代谢受限可能是谷子耐旱性增强的代谢过程之一。本研究提倡将驯化作为一种有效策略，以减轻干旱引起的谷子代谢紊乱的负面影响，从而增强全球粮食安全并促进可持续农业系统。
