European Journal of Sustainable Agroecosystems

Background: Chickpea (Cicer arietinum L.) is the world's second most important grain legume and a critical source of dietary protein for millions of people, yet its productivity is severely constrained by heat stress during the reproductive stage, which impairs pollen viability, fertilisation, pod set, and seed development. As global mean temperatures continue to rise, understanding the biochemical basis of genotypic variation in heat tolerance has become a research priority. Metabolomics, which captures the terminal products of gene expression and cellular regulation, has emerged as a powerful lens through which heat-responsive biochemical reprogramming in chickpea can be resolved at genotype-specific resolution.
Objective: This review synthesises the existing peer-reviewed literature on metabolomic and lipidomic profiling of heat-stressed chickpea genotypes, with the aim of consolidating analytical approaches, comparing findings across contrasting genotypes and tissues, identifying converging and divergent biomarker patterns, and mapping unresolved research gaps.
Sources of literature: A structured search of Scopus, Web of Science, PubMed, Google Scholar, and ScienceDirect was conducted for records published between 2015 and 2025, supplemented by relevant landmark studies published earlier. Following a PRISMA-style screening process, 38 core studies addressing chickpea heat-stress physiology, metabolomics, lipidomics, transcriptomics, and multi-omics integration were retained for thematic synthesis.
Major findings: Widely targeted and untargeted metabolomic studies on flower buds and seeds of contrasting genotypes (heat-tolerant PI518255 and heat-sensitive PI598080) consistently show large-scale metabolic reprogramming under heat stress, with heat-tolerant genotypes accumulating elevated flavonoids, phenolic acids, and specific membrane lipids, while lysine degradation, butanoate metabolism, and isoflavonoid biosynthesis pathways are recurrently enriched. Osmolyte accumulation, particularly proline and soluble sugars, differentiates tolerant from sensitive genotypes across both heat and drought studies, and lipidomic remodelling of phosphatidylethanolamine, phosphatidylinositol, and galactolipid species tracks membrane thermostability. Integration with transcriptomic and QTL data has begun to identify candidate heat-shock protein and transcription-factor loci that co-localise with metabolic shifts.
Research gaps: Most metabolomic evidence derives from a small number of contrasting genotype pairs under controlled-environment conditions, with limited field validation across diverse germplasm, environments, and years. True multi-omics integration linking metabolomics with genomics and phenomics at scale remains rare, and metabolite-based markers have not yet been operationalised in marker-assisted or genomic selection pipelines.
Conclusion: Metabolomics offers substantial promise for dissecting heat tolerance mechanisms and generating biomarkers for breeding in chickpea, but realising this promise will require standardised, field-validated, multi-environment metabolomic studies integrated with genomic and phenomic data streams.