Nitrogen Management to Optimize Sugar Beet Production in the RED River Valley.

Fertilizer nitrogen (N) is a critical component of sugar beet (Beta vulgarisL.) production. Root yield, extractable sucrose- and purity percentage are greatly impacted by fertilizer N application rate. Optimum fertilizer N management promotes vigorous early season vegetative growth, canopy closure, which allows sugar beet for efficient use of solar energy to increase yield. The current fertilizer N recommendation for sugar beet (after considering residual N of 4 ft soil depth) is 130 lb N ac^-1 to achieve the yield goal of 20 t ac^-1. This multi-location on-farm fertilizer N rate trial was conducted to determine whether current fertilizer N recommendation still holds the promise to achieve the maximum yield and quality across the Red River Valley (RRV). During 2015-17 growing season, on-farm fertilizer N trials have been conducted across the Red River Valley.