Effect of phosphorus (P) application on nutrient uptake, biomass, pod and seed formation in cowpea (Vigna unguiculata (L.) Walp]): poster presented at the 7th International Conference of the Africa Soil Science Society: critical soil solutions for sustainable development in Africa, 29 May - 1 June, Burkina Faso, Ouagadougou - Suzuki, K.; Fatokun, C.A.; Boukar, O. (African Soil Science Society, 2016)