In a field experiment near Göttingen the influence of density and time of emergence of Chenopodium album and Chamomilla recutita on the competition between sugar beet and weeds was studied. For this purpose, increasing densities of weeds emerging at different growth stages of sugar beet (2–4 and 6–8 leaf stage) were tested. In recent investigations, different relationships between weed density and yield loss were observed for C. album emerging at different growth stages of sugar beet. The different growth patterns, the shading and the relationships between yield loss and weed dry matter are presented for both weed species. Reasons for the different relationships between yield loss and density of weeds emerging at different dates are analyzed.
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