Management of weeds in irrigated rice cultivation in the middle valley of the Senegal River

In the valley of the Senegal River, weeds represent one of the major constraints of irrigated rice cultivation. In that context, the development of efficient and adapted methods for better management of weeds is critical. This study aims at evaluating the efficacy of the combination of two formulations of herbicides (Eros Gold and Londax) and two sowing methods (direct sowing and transplanting) on rice weeds in a Split Plot design with three replicates. The weed flora was evaluated through phytosociological surveys with three observations: before heading, after heading and ripening stages of rice. Floristic surveys identified 16 families, 25 genera and 28 species of weeds. In addition, the results showed that Eros Gold had a significant effect with sowing methods on the decrease of sedges and grasses density but more specifically on the abundance-dominance of broadleaf weeds (dicotyledons) before and during heading stages of rice. On family groups, Cyperaceae (15.39 ind/ha), grasses (15.72 ind/ha) and dicotyledons (24.94 ind/ha) are more sensitive to Eros Gold in broadcast sowing than in transplanting mode with 26, 56 ind/ha, 26.50ind / ha and 27.94 ind/ha respectively.