Abstract
Sugarbeet production on soils with a long history of manure or dairy compost additions can be challenging. Often containing more than 400 lb N/acre, these soils are much higher in nitrogen than is recommended for optimal sugarbeet productivity. High nitrogen is known to reduce sugar % and increase impurities in sugar juice. This results in a higher sugar purity penalty which then reduces the beet payment to growers. In addition to manured fields, high nitrogen can also be a problem for sugarbeets following onion or potato rotations, which are often highly fertilized. Unable to reduce soil nitrogen, growers have few options available to them. Selecting a variety that performs well under these conditions therefore becomes critical. While there is some anecdotal evidence suggesting certain varieties do perform better than others under high nitrogen conditions, these claims have not been tested. This study reports the findings of Agridata analysis and field trial research investigating the performance of 30 commercial sugarbeet varieties under normal (250 lb N/A) and high (450 lb N/A) nitrogen growing conditions. Although most varieties showed increased yield, overwhelmingly, high-N led to reduced sugar %, higher conductivity, and greater sugar juice impurities in the form of higher brei nitrates. Despite this, there were clearly some varieties that performed better than others and were able to overcome their reduced sugar % and purity penalties by delivering much higher yields. This work provides variety recommendations for growers with high nitrogen soils.