Physiological and metabolomics responses of two wheat (Triticum aestivum L.) genotypes differing in grain cadmium accumulation
Physiological and metabolomics responses of two wheat (Triticum aestivum L.) genotypes differing in grain cadmium accumulation
复制标题
两种小麦（Triticum aestivum L.）基因型籽粒镉积累不同的生理和代谢组学反应
DOI：
10.1016/j.scitotenv.2021.145345
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发表时间：
2021-02-06
影响因子：
9.8
通讯作者：
Yang, Xiaoe
中科院分区：
文献类型：
--
作者：
Lu, Min;Yu, Song;Yang, Xiaoe
为减少食物链镉污染，筛选和培育低镉积累基因型已受到越来越多的关注。然而，涉及镉的耐受性和积累的机制尚未完全了解。研究了两种小麦（Triticum aestivum L.）基因型--籽粒低镉积累基因型（矮抗58、AK 58）和籽粒高镉积累基因型（珍麦10、ZM 10）在无镉和镉胁迫下水培7 d的生理响应和代谢组学特征。结果表明，AK 58是一个具有较强抗氧化系统能力的耐镉基因型。此外，AK 58根系细胞壁对Cd的吸附量高于ZM 10，其中果胶和半纤维素对Cd的吸附起重要作用。此外，亚细胞分布表明，镉螯合在液泡中是另一种耐受机制在AK 58。同时，代谢组学分析表明，在AK 58中，苯丙氨酸代谢，丙氨酸，天冬氨酸和谷氨酸代谢，异喹啉生物碱生物合成，精氨酸和脯氨酸代谢，精氨酸生物合成以及乙醛酸和二羧酸代谢与抗氧化防御系统，细胞壁生物合成以及植物螯合素与其他有机配体的代谢高度相关，在植物根系的镉耐性和镉固定机制中起着重要作用。这些新的发现将有助于分子标记辅助筛选和培育小麦低镉积累基因型。(C)2021爱思唯尔有限公司版权所有。
To reduce cadmium (Cd) pollution of food chains, screening and breeding of low-Cd-accumulating genotypes have received increasing attention. However, the mechanisms involving Cd tolerance and accumulation are not fully understood. Here, we investigated the physiological responses and metabolomics profiling on two wheat (Triticum aestivum L) genotypes, a low-Cd-accumulating genotype in grains (Aikang58, AK58) and a high-Cd-accumulating genotype in grains (Zhenmai10, ZM10), in hydroponic culture treated without/with Cd for 7 days. The results showed that AK58 was a Cd tolerant genotype with higher capacity of antioxidant systems in root. In addition, the concentrations of Cd bound to root cell walls were higher in AK58 than ZM10, of which pectin and hemicellulose played important roles in Cd binding. Moreover, subcellular distribution manifested that Cd sequestrated in the vacuoles was another tolerance mechanism in AK58. Simultaneously, metabolomics profiling showed that, in AK58, phenylalanine metabolism, alanine, aspartate and glutamate metabolism, isoquinoline alkaloid biosynthesis, arginine and proline metabolism, arginine biosynthesis and glyoxylate and dicarboxylate metabolism are highly related to antioxidant defense system, cell wall biosynthesis and metabolisms of phytochelatins together with other organic ligands, playing crucial roles in Cd tolerance and Cd fixation mechanisms in roots. These novel findings should be useful for moleadar assisted screening and breeding of low Cd-accumulating genotypes for wheat crop. (C) 2021 Elsevier B.V. All rights reserved.