Importance of harvesting system and variety for storage losses of sugar beet

Damage resulting from harvest operations increases the storage losses of sugar beet. Because of different equipment, the kind and extent of damage may differ between harvesting systems. The objective of the study was to analyze (I) the impact of different harvesting systems and cleaning intensities on damages of sugar beet, and furthermore, (II) the effect of these damages on storage losses. In 2015 and 2016 at four sites, two sugar beet varieties were harvested with two six-row harvesters (axial rollers versus turbines for cleaning) using three cleaning intensities with three replicates in tracks of 200 m length. Roots were stored in a climate container at 9 degrees C for 5 and 12 weeks. The results show that the diameter of root tip breakage and surface damage increased with cleaning intensity. Marked differences occurred among varieties and sites. The factor analysis indicates that the extent of damage (root tip breakage, surface damage) had a considerable impact on the infestation with mold and rots, the accumulation of invert sugar and sugar losses after storage. However, the higher root tip breakage of beets harvested by harvester 2 was accompanied by lower sugar losses than in harvester 1 after 12 weeks storage, in particular with the aggressive cleaning intensity. The marked impact of the cleaning intensity emphasizes the importance of the operator and of the optimal setting of the harvester for a good harvest quality and thus storability of sugar beet.