An ancient super allele of the Vrs1 gene driving the recent success in modern barley improvement through optimising spike architecture

Abstract

Highlights 1 A deficiens morphology-associated allele, Vrs1.t1 , was identified with two F 2 populations. Vrs1.t1 in two-rowed deficiens barley exhibited increased spikelet length, grain number and grain size. The Vrs1.t1 originated in the Fertile Crescent and dispersed with the Neolithic migrations. Improved yield potential is the goal of barley domestication and cultivation. During this process, two-rowed and six-rowed barley types emerged and have been utilised in breeding and production. The six-rowed type could produce three times as many grains as its ancestral two-rowed forms, thus dominating barley cultivation for thousands of years. The deficiens form of the two-rowed type, characterised by extremely suppressed lateral spikelets, has gained dominance over the past few decades in b