Submitted to: American Society of Sugarbeet Technologists
Publication Type: Abstract Only
Publication Acceptance Date: May 7, 2001
Publication Date: N/A
Technical Abstract: In recent years root-rots have become more prevalent throughout MN and eastern ND. Any increase of root-rots in the field will be accompanied by an increase in the proportion of roots with rot that are placed in storage piles. Information on the effects of root-rot severity on initial quality and storability would assist grower and agriculturalists when determining the level of disease severity that would justify not harvesting a field., or if roots from diseased fields should be segregated and processed first. Three fields south of Moorhead, MN were sampled in 2000. Roots from each field were divided into four groups, based upon root-rot severity. The most severely infected roots were substantially lower in extractable sugar per ton and had considerably higher respiration rates. Respiration rates of roots classified as moderate or severe increased over time while rates for roots with no rot remained relatively constant. The higher respiration rates of the diseased roots would increase pile temperatures, increasing storage losses of adjacent healthy roots. Carbohydrate impurity concentration also increased with disease severity. The concentration of the invert sugars, glucose and fructose, increased with disease severity, although the trisaccharide content was slightly lower in the most severely diseased roots. Raffinose was the major trisaccharide present. The concentration of all impurities declined with prolonged storage regardless of the severity of disease symptoms. The results present in this report are based on a few samples collected in a single year and should be considered preliminary. Continuing research in this area will provide more reliable information for making decision regarding harvesting and storing diseased roots.