The effect of VRN1 genes on important agronomic traits in high-yielding Canadian soft white spring wheat

For reproductive success, flowering time must synchronize with favourable environmental conditions. Vernalization genes play a major role in accelerating or delaying the time to flowering. We studied how different vernalization (VRN1) gene combinations alter days to flowering and maturity and consequently the effect on grain yield and other agronomic traits. The study focussed on the effect of the VRN1 gene series (Vrn-A1, Vrn-B1 and Vrn-D1) and their combinations. The Vrn gene group Vrn-A1a, Vrn-B1, vrn-D1 was the earliest to flower and mature, while Vrn-A1b, Vrn-B1, vrn-D1 was the latest to flower. Spring wheat lines with vrn-A1, Vrn-B1, Vrn-D1 were the highest yielding and matured at a similar time as those having vernalization genes Vrn-A1a, Vrn-B1 and Vrn-D1. The findings of this study suggest that the presence of Vrn-D1 has a direct or indirect role in producing higher grain yield. We therefore suggest the introduction of Vrn-D1 allele into higher-yielding classes within Canadian spring wheat germplasm.