Influence of Poultry Droppings on the Production and Mineral Profile of Cowpea (Vigna unguiculata (L.) Walp) in Kombé (Brazzaville, Congo)

Abstract

Cowpea (Vigna unguiculata (L.) Walp.) is one of the most important seed legumes in the tropics and subtropics. It is an important staple in sub-Saharan Africa, particularly in the arid savannahs of West Africa. The present study conducted in the Kombé area (Brazzaville) aims to assess the impact of poultry droppings on the yield and mineral profile of cowpea. Seeds of three cowpea cultivars (C1, C2, C3) were sown in a completely randomised system in two plots. Prior to sowing, a treatment of one dose of poultry droppings was applied in one of the two plots, which was named fertilised plot containing treatments C1D1, C2D1 and C3D1. The plot without droppings was the control plot with treatments C1D0, C2D0 and C3D0. The biomass of leaves, pods and seeds was assessed by the harvesting method followed by drying and weighing. Chemical data of leaves and soils were obtained after laboratory analysis. The results show that leaf biomass, pod biomass and seed biomass ranged from 1.8 t DM/ha to 3.4 t DM/ha, 960.2 kg/ha to 1706 kg DM/ha and 563.4 kg DM/ha to 1263.7 kg DM/ha respectively. Treatments C1D1 and C3D1 were respectively the most productive in leaf biomass and pod and seed biomass. The nitrogen and phosphorus contents in the leaves do not seem to be influenced by the addition of poultry droppings. However, these contents are improved in the soil after the application of poultry droppings. Poultry droppings have a beneficial effect on yield in terms of leaf, pod and seed biomass. Poultry droppings may be useful as an organic fertilizer for cowpea cultivation.