Sucrose production as affected by root yield and sucrose concentration of sugarbeets

Refined sugar production of sugarbeets (Beta vulgaris L.) is based on the product of root yield and extractable sucrose concentration. Conditions that affect either of these components may either increase or decrease refined sugar yield. Therefore, it is of prime importance to use practices and conditions that provide adequate top and root growth while maintaining sufficiently high sucrose concentration and purity for profitable sucrose extraction and yield. An inherent inverse relationship exists between sugarbeet root yield and wet root sucrose concentration (9,10,15). Increasing root yields by plant breeding, genetic selection, nitrogen (N) fertilization, agronomic practices, and environmental conditions will generally decrease sucrose concentration (5,14). Milford (13) and Doney (7,8) have both reported an inverse relationship between root cell size and sucrose concentration, and have suggested that the negative correlation results from the opposite effects of cell size on root yield and sucrose concentration. Large cells produce large roots with high root yields and low sucrose concentration; whereas small cells produce small roots with low root yields and high sucrose concentration