Changes in root morphology with yield level of sugar beet

Abstract

The high yield level sugar beet has reached in the past years might have altered the morphology of the storage root. The study thus aimed at analyzing storage root diameter and length in relation to yield under various environmental conditions. For that purpose, data of various field and pot experiments were included covering a broad range of storage root diameters and yield levels of sugar beet. It turned out that there was a close relationship between storage root diameter and root yield, which was not affected by different environmental conditions (site, year). Furthermore, breeding progress had obviously not changed this relation, as it was not affected by varieties. Results from pot experiments could well be compared with field trial data. In field trials, storage root length did not exceed 25cm independent of yield level, whereas in pot experiments plants formed longer storage roots with higher yield levels. It is discussed that increasing penetration resistance in soil could limit the further expansion of the storage root diameter. A more aboveground growth of the storage root with increasing yield level, however, will make yield estimates based on root diameter more difficult.