Molecular and genomics-assisted breeding strategies for enhancing abiotic stress resilience in major cereals

The global population is projected to reach about 9.7 billion by 2050. This expected growth will necessitate sustainable and sufficient crop production, particularly in developing countries where stresses, land degradation and limited agricultural resources are remain major challenges. Developing stress-resilient crop varieties is therefore essential to reduce yield losses and strengthen global food security under changing climatic conditions. Conventional plant breeding has achieved remarkable successes in increasing agricultural productivity, particularly through steady increases in crop yield potential. However, further genetic improvement of abiotic-stress adaptation remains difficult because stress responses are often polygenic, strongly influenced by genotype × environment (G × E) interaction and expressed differently across target environments. Over the past decade, genomics-assisted breeding (GAB) has expanded opportunities to identify, predict and modify stress-adaptive genetic variation, yet translation of genomic discoveries into stable genetic gain remains inconsistent. Accordingly, this review critically examines current progress in GAB through three questions that define the translation of genomic information into genetic gain: (a) why do many stress-associated loci and candidate genes fail to progress from discovery to breeding deployment; (b) how should major-effect loci and distributed polygenic variation be exploited through marker-assisted introgression and pyramiding, genome-wide prediction and targeted genetic modification (c) and how can prediction and selection be made more reliable under G × E and across the target population of environments? Answers to these questions will help to determine how effectively genomic discoveries can be translated into predictive and deployable breeding frameworks that improve selection accuracy and sustain genetic gain across diverse stress-prone environments.