QTL for Winter Hardiness in Sugar Beet (Beta vulgaris ssp. vulgaris L.)

Growing sugar beet (Beta vulgaris L. ssp. vulgaris var. altissima) as a winter crop in cool temperate regions requires the development of a winter sugar beet with controlled bolting and sufficient winter hardiness. To identify genetic factors for winter hardiness, 224 F₃ families were derived from crossing a winter hardy with a winter susceptible sugar beet inbred line. This population was sown in August 2012 in replicated overwintering trials at three field locations in Northern and central Germany. Survival rate was determined in May, 2013 and ranged from 5 to 91 % for F₃families across locations. The genetic effect on survival rate was highly significant (p < 0.0001) and had a heritability of 89%.

A linkage map was constructed and two major QTL could be mapped in each field location. Together these QTL explain more than 30% of the phenotypic variation for winter hardiness and should be suitable for marker assisted selection of winter hardiness in sugar beet.