Pangenome analysis provides insights into legume evolution and breeding

Abstract

Grain legumes hold great promise for advancing sustainable agriculture. Although the evolutionary history of legume species has been investigated, the conserved mechanisms that drive adaptive evolution and govern agronomic improvement remain elusive. Here we present high-quality genome assemblies for nine widely consumed pulses, including common bean, chickpea, pea, lentil, faba bean, pigeon pea, cowpea, mung bean and hyacinth bean. Pangenome analysis reveals the expansion of distinct gene sets in cool-season and warm-season legumes, highlighting the role of gene birth and duplication in the autoregulation of nodulation. Notably, hundreds of genes undergo convergent selection during the evolution of legumes, affecting agronomic traits such as seed weight. In addition, we demonstrate that tandem amplification of transposable elements in gene-depleted regions has a crucial role in driving genome enlargement and the formation of regulatory elements in cool-season legumes. Our results provide insights into the molecular mechanisms underlying the diversification of legumes and represent a valuable resource for facilitating legume breeding.