Effect of Time and Rate of Application of Nitrogen and Date of Harvest on the Yield and Sucrose Content of Sugar Beets¹

Abstract

In a 3‐year experiment on Brookston clay loam, the effect of time and rate of application of nitrogen on the yield and sucrose content of sugar beets was studied. Maximum yield of sugar was obtained when nitrogen was applied as a preplant at 90 or 120 pounds per acre or as a sidedressing in mid‐June at 60 or 90 pounds per acre. A harvest delay of 28 days resulted in an increase of 1017 pounds of sugar per acre, representing an average increase of 36 pounds per acre per day. The initial 14 days of harvest delay resulted in an increase of 638 pounds of sugar, or a daily increase of 46 pounds per acre, as compared to an increase of 379 pounds of sugar or a daily increase of 27 pounds per acre for the last 14 days delayed harvest. The date of harvest was the most important factor affecting the sucrose content of beets. The order of importance of the variables on differences in sucrose content was: Date of harvest >> Time of nitrogen application > Rate of nitrogen application > Interactions. The rate of nitrogen application and date of harvest were about equal in effect and accounted for the majority of the variation in root yield. The order of importance of the variables on differences in root yield was: Rate of nitrogen application ≃ Date of harvest >> Time of nitrogen application > Interactions. The date of harvest was the most important factor contributing to differences in sugar yield. The order of importance of the variables on the variation in sugar yield was: Date of harvest >> Rate of nitrogen application > Time of nitrogen application > Interactions.

Genotype and Variable Nitrogen Effects on Tuber Yield and Quality for Red Fresh Market Potatoes in Minnesota

“…The release of nitrogen into the environment is a problem with standard cultivation practices for a variety of crops. The effects of variable timing, spacing, and rate of N fertilizer application has been studied in wheat (Triticum aestivum) [4,5], barley (Hordeum vulgare) [6], sugar beet (Beta vulgaris) [7], safflower (Carthamus tinctorius) [8], potato [5,[9][10][11][12][13], and many other crops. However, changes in management can make limited progress without corresponding changes in the genetics of the crops themselves [14].…”