Seed is one of the most important factors in the production of sugar beet roots. Only ten to thirty percent of the harvested seeds have good quality for root production. In order to increase the yield of sugar beet seed of optimal quality, a profound know- ledge of the main parameters that influence germination ability for a given hybrid is required. The main aim of this investiga- tion is to develop a physiological working scheme of seed deve- lopment of sugar beet. This scheme should allow new insights in the parameters that are important for seed development and final seed quality. Based on this knowledge, we will optimize the pro- duction and processing of sugar beet seed. For this purpose the physiological, morphological and chemical seed characteristics that may influence the seed quality will be quantified for five hybrids. Furthermore the plant structure of the mother plants, caliber ratios and germination potency of the seeds .....