Superior haplotypes for transforming crop breeding

Climate change and the rapid rise in the global population are exerting immense pressure on limited natural and genetic resources. Meeting future food demands requires accelerated genetic gain under rapidly changing environmental conditions. Advances in genomics, supported by large-scale sequencing of diverse crop germplasm, have enabled the mapping of key genes and the development of climate-resilient varieties. However, the utility of these genes and their associated haplotypes is often limited, as they are specific to particular ecologies and populations, restricting their broader introgression into various breeding programmes. The concept of superior haplotypes can help us address these limitations by identifying the allelic combination that confers a desirable trait with stable, consistent and significant performance across diverse panels and environments. For instance, in rice, the GS3-H1 haplotype is associated with improved grain size and yield potential, while Sub1A-1 confers superior submergence tolerance compared to Sub1A-2. Similarly, in rapeseed, Hap1 of qOCA3 and qOCC6 is associated with higher oil content. Building on such examples, this review systematically catalogues superior haplotypes identified across major crops, highlights key research gaps, and outlines a roadmap for their deployment in genomic-assisted breeding to enhance crop productivity, adaptability, and resilience.