Metabolomics for High- and Low-Temperature Stress Responses and Tolerance in Plants

High temperature or heat stress (HS) and low temperature or cold stress (CS) are critical environmental elements affecting plant growth and development, and the continuous seasonal and daily temperature changes affect plants and have different effects depending on whether they stay within a natural temperature range for each species or whether the range’s extremes are reached. However, “cold acclimation” or “acquired thermotolerance,” adaptive processes by which plants increase their chilling or heat tolerance in response to a previous low nonfreezing or high temperature exposure, respectively, can extend the temperature range of survival in some species. The substantial role of central amino acids, carbohydrates, nitrogen metabolisms, and metabolites complicated in biosynthesis and catalyzing actions play a role in HS and CS response and help plants cope with them. These metabolites appeared to be an integral component of reprogramming the metabolome under temperature stress, which is one aspect of metabolism that is constant across all of the temperature–stress metabolomic studies conducted to date. This chapter emphasizes how crops under HS and CS may be improved using a cutting-edge plant metabolomics method. Developing plants with specific characteristics using integrated omics (metabolites and transcriptomes) and metabolomics-assisted breeding are new directions for future research to increase plants’ tolerance to HS and CS to achieve abundance in their productivity and overcome world hunger problems.