Agronomy Dept., University of Florida, Gainesville, FL, United States of America.
West Florida Research and Education Center, University of Florida, Jay, FL, United States of America.
PLoS One. 2018 Jun 13;13(6):e0197919. doi: 10.1371/journal.pone.0197919. eCollection 2018.
Genetic improvement for stress tolerance requires a solid understanding of biochemical processes involved with different physiological mechanisms and their relationships with different traits. The objective of this study was to demonstrate genetic variability in altered metabolic levels in a panel of six wheat genotypes in contrasting temperature regimes, and to quantify the correlation between those metabolites with different traits. In a controlled environment experiment, heat stress (35:28 ± 0.08°C) was initiated 10 days after anthesis. Flag leaves were collected 10 days after heat treatment to employ an untargeted metabolomics profiling using LC-HRMS based technique called IROA. High temperature stress produced significant genetic variations for cell and thylakoid membrane damage, and yield related traits. 64 known metabolites accumulated 1.5 fold of higher or lower due to high temperature stress. In general, metabolites that increased the most under heat stress (L-tryptophan, pipecolate) showed negative correlation with different traits. Contrary, the metabolites that decreased the most under heat stress (drummondol, anthranilate) showed positive correlation with the traits. Aminoacyl-tRNA biosysnthesis and plant secondary metabolite biosynthesis pathways were most impacted by high temperature stress. The robustness of metabolic change and their relationship with phenotypes renders those metabolites as potential bio-markers for genetic improvement.
遗传改良以提高抗逆性需要对不同生理机制所涉及的生化过程及其与不同性状的关系有深入的了解。本研究的目的是展示在不同温度条件下的 6 个小麦基因型中改变的代谢水平的遗传变异，并量化这些代谢物与不同性状之间的相关性。在受控环境实验中，开花后 10 天开始进行热胁迫（35:28 ± 0.08°C）。热处理后 10 天采集旗叶，采用基于 LC-HRMS 的 IROA 技术进行非靶向代谢组学分析。高温胁迫对细胞和类囊体膜损伤以及与产量相关的性状产生了显著的遗传变异。由于高温胁迫，64 种已知代谢物的积累增加了 1.5 倍或减少了 1.5 倍。一般来说，在热胁迫下增加最多的代谢物（L-色氨酸、哌可酸）与不同性状呈负相关。相反，在热胁迫下减少最多的代谢物（drummondol、邻氨基苯甲酸）与性状呈正相关。高温胁迫对氨基酸酰基-tRNA 生物合成和植物次生代谢物生物合成途径的影响最大。代谢变化的稳健性及其与表型的关系使这些代谢物成为遗传改良的潜在生物标志物。
