Rational Integrated Weed Management in Alfalfa Seed Production in West-Central France

This study, led by FNAMS with INRA and ARVALIS, evaluates integrated weed management strategies in alfalfa seed production in west-central France. Over three seasons, researchers surveyed 66 fields using a modified Barralis density scale at key growth stages to record adventice species frequency and density. They also analyzed seed samples before and after cleaning to assess contamination rates. Results show high weed diversity in fields but low contamination in cleaned batches. The findings demonstrate that targeted agronomic practices within crop rotation and intercrop periods can effectively reduce the most problematic weeds, supporting seed purity certification despite reduced herbicide options.