SOIL AND WATER CONTROL IN AGRICULTURAL PRODUCTION: CASE OF RICE ON THE IRRIGATED PERIMETER OF TANGBÉDJI IN THE ZOGBODOMEY’S MUNICIPALITY, BENIN

Abstract

The purpose of this study is to assess the impact of soil fertility and water control on rice yield in the Tangbédji perimeter. A survey and a monitoring were carried out on all active rice farmers during the 2020 agricultural campaign. The analysis of the physico-chemical properties of the soils indicates a sandy clay texture with low permeability of 1.6.10-5 m/s. Organic matter, Nitrogen, Phosphorus and Potassium average contents are respectively of 2.61 %, 0.07%, 22.5 ppm and 1.08 meq/100g. This shows that the soil is suitable for rice cultivation. The multitude of technical itineraries adopted on the perimeter generates differences in terms of mineral fertilization, plot maintenance and yield. Despite the potential in cultivable land, in water and the high level of soil fertility, the average yield obtained of 0.96 t/ha is lower than the expected yield in rainfed lowlands of 4 to 5 t/ha. To achieve the optimal yield of rice cultivation in Tangbédji, it is urgent to respect the technical itinerary recommended by the National Institute for Agricultural Research (INRAB) for the variety IR 841. On the other hand, for total water control over the 540 hectares, it is necessary to provide for a maximum peak flow of 6.17 l/s/ha and an equipment flow of 3.3 m3/s in head of the irrigation network.