Evaluation of two chemical weed control systems in sugar beet in Germany and the Russian Federation

Roundup Ready® sugar beets are widely grown in the USA since their market introduction in 2005. The system has proven to be cost-efficient and reliable. However, the negative social image among consumers and politicians has prohibited the adoption of this technology in Europe. Seven field experiments were conducted over three years in Germany and the Russian Federation to compare weed control efficacy and sugar beet yields of post-emergent glyphosate applications with conventional selective herbicides. Although weed infestations at the Russian sites were higher than in Germany, weed control efficacies were similar at both locations ranging between 78% and 100%. Glyphosate applications resulted in significantly higher weed control efficacies than the conventional herbicides in four out of 7 experiments. In five experiments, a single glyphosate application gave equal weed control efficacy as two and three glyphosate applications. White sugar yield was always higher in the weed control treatments than in the untreated plots. There was no yield difference between treatments based on glyphosate and conventional herbicide applications in 6 out of 7 experiments. The results demonstrate a slight benefit of the glyphosate-based weed control program compared to the conventional herbicide system in terms of weed control efficacy.