Drought-Resilient Crops for Sustainable Agriculture: Genetic, Physiological, and Agronomic Advances

Abstract

Drought constitutes one of the most pervasive abiotic constraints limiting global crop productivity, with its frequency and intensity projected to increase substantially under ongoing climate change. This narrative review synthesises contemporary evidence on the genetic, physiological, and agronomic dimensions of drought resilience in major food crops, drawing on peer-reviewed literature published primarily between 2000 and 2026. Physiologically, drought impairs stomatal conductance, suppresses photosynthetic carbon assimilation, disturbs osmotic equilibrium, and restricts root-mediated water acquisition, with reproductive stages being disproportionately vulnerable. At the genetic level, the deployment of quantitative trait loci (QTL) mapping, transcription-factor engineering, CRISPR-Cas9 genome editing, and the overexpression of stress-responsive functional genes has opened novel avenues for enhancing tolerance without compromising yield potential. Breeding programmes have increasingly integrated marker-assisted selection (MAS) and genomic selection to accelerate genetic gain, whilst high-throughput phenotyping platforms now enable rapid assessment of drought-adaptive traits at a population scale. Agronomic strategies, including deficit irrigation, conservation tillage, intercropping, and application of plant growth-promoting rhizobacteria (PGPR), provide complementary levers for sustaining productivity under water-limited conditions. Emerging integrative approaches that combine multi-omics, digital precision agriculture, and policy-enabled climate-smart frameworks are highlighted as critical pathways for translating laboratory and field insights into scalable solutions. The review identifies persistent knowledge gaps—including the limited translation of genomic advances to smallholder contexts and the underexplored potential of microbiome engineering—and calls for a convergence of disciplinary expertise, equitable technology transfer, and coherent policy support to achieve drought-resilient food systems globally.