Sugarbeet Yield and Quality Response to Nitrogen Fertilizer Rate and In-Season Prediction of Yield and Quality Using Active-Optical Sensor

Abstract

Nitrogen (N) management is one of the important factors in sugarbeet production. Under-application of N-fertilizer results in lower root yield while over-application of N-fertilizer can result in decreased sugar concentration and recoverable sugar. In recent years active-optical sensors have been investigated for in-season prediction of sugarbeet yield and quality and to make N management decisions. This study was conducted at four sites in the Red River Valley to determine the sugarbeet yield and quality response to N fertilizer rates and to determine the relationship of NDVI with sugarbeet yield and quality. The yield response to N fertilizer rates was significantly quadratic, however, sugar concentration did not show response to N fertilizer rates. In-season NDVI readings were strongly related with root yield and sugar yield. Active sensing during the growing seasons shows promise as a means to predict sugarbeet root yield and sugar yield.