Sink development and dry matter distribution in storage root crops

Events during early development are examined for their contribution to dry matter distribution in the mature plant. It is concluded that timing of initiation of the storage root is not a major cause of differences between cultivars of carrot. These may airse from differences in the control of partitioning of assimilate at storage organ initiation. Root crop species may be affected differently by environmental factors such as density as a result of different thresholds of response of sink development to source stimuli.