Effect of water management practices on rice productivity in the Lower Ouémé Valley in Southern Benin (West Africa)

Rice is a staple food in Benin, where domestic production remains insufficient to meet national demand, resulting in a strong reliance on imports. The Lower Ouémé Valley (LOV), characterized by extensive wetlands with high soil and hydrological potential, provides favorable conditions for sustainable intensification of rice production. However, this potential remains underexploited due to climate variability, inadequate water management, and suboptimal agronomic practices. This research aims to assess the effects of two water management and agricultural development approaches (Smart-valleys and the conventional system) and three irrigation regimes (variable water level irrigation IR1, low water level irrigation IR2, and intermittent irrigation IR3) on rice agronomic performance in the LOV. Field experiments were conducted in the Awogba lowland, Silico-Dogbamey, Adjohoun municipality, using a split-plot design with two replications. An exploratory survey was also conducted among rice farmers to characterize crop management and water management practices. The results show that the Smart-valleys approach reduced water consumption by more than half, from 16,433 m 3 ha⁻ 1 under the conventional system to 7478 m 3 ha⁻ 1 , while increasing mean grain yield by 2.3 t ha⁻ 1 and water productivity by 0.46 kg m⁻ 3 . Among the irrigation regimes, IR1 achieved the highest grain yield (6.3 t ha⁻ 1 ), whereas IR3 resulted in the highest water productivity (1.14 kg m⁻ 3 ), with water consumption reduced to 8795 m 3 ha⁻ 1 . The Smart-valleys–IR3 combination produced the best overall agronomic performance, with a grain yield of 8.3 t ha⁻ 1 , water productivity of 1.74 kg m⁻ 3 , and substantially lower water consumption (4864 m 3 ha⁻ 1 ). These findings highlight the potential of combining water-controlling field development with intermittent irrigation to simultaneously improve rice productivity and water-use efficiency. This strategy offers a promising pathway toward more water-efficient, productive, and climate-resilient rice production in the Lower Ouémé Valley.