Start Date: 2012
Principal Investigator: Albert Sims
Organization: University of Minnesota, Department of Soil, Water, and Climate
Status: Complete
Background Info
Nitrogen (N) management is critical in sugar beet production. Too little nitrogen early in the growing season can reduce root yield, while too much later can reduce root quality. Growers are interested in increasing N use efficiency in sugar beet production by using alternative N management strategies, such as spring-applied N instead of fall-applied or applying enhanced efficiency nitrogen sources such as ESN (Environmentally Smart Nitrogen). Too much spring-applied urea can reduce sugar beet production. Can ESN ease this problem? Outside the Midwest, sugar beets often need very large quantities of N. Loss of N through denitrification is one hypothesis as to why extra N is needed. Will the use of ESN preserve nitrogen for a longer period of time than urea?
Objectives
Determine if sugar beet root yield and quality are effected by timing of N fertilization
Determine if sugar beet stands, root yield and quality, and N use efficiency can be enhanced by using a polycoated urea (PCU) either alone or mized with urea
Determine if N loss through denitrification is effected by the source of N or the timing of its application
Key Findings
During the three years of this trial, sugar beet root yield and quality did not differ among: time (fall vs spring) of N fertilizer application, n sources (ESN vs urea), N rates (two N rates were used), this was quite different than results of earlier experiments in the same growing area.
N losses through denitrification was not great during any year of the trial though there were periods of excessive soil wetness. Some difference among N sources, results are still being interpreted.