African Journal of

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12296

Full Length Research Paper

Evaluation of phosphorus fertilizer rates for maize and sources for cowpea on different soil types in southwestern Nigeria

G. O. Kolawole*, A. O. Olayiwola, O. Ige, G. O. Oyediran and B. A. Lawal
Department of Agronomy, Ladoke Akintola University of Technology (LAUTECH), PMB 4000, Ogbomoso, Oyo State, Nigeria.
Email: [email protected]

  •  Published: 14 June 2010



Flexible phosphorus (P) fertilizer rate recommendation could be based on variations in soil characteristics that affect yield responses. Experiments were conducted in the Department of Agronomy, LAUTECH, on the effects of P rates on maize and P sources on cowpea in four soil types. On average, soil types and P rates influenced maize height and grain yield. Iwo and Egbeda soils supported taller plants than Itagunmodi soil. Phosphorus fertilization enhanced height and grain yield compared with no P. To optimize maize grain yield for Itagunmodi and Egbeda soils, application of 15 kg P2O5 ha-1 was sufficient while for Majeroku and Iwo, it was 30 and 75 kg P2O5 ha-1, respectively. Cowpea grain yield and P uptake were significantly affected by soil types and P sources. Iwo and Egbeda soils supported higher grain weights and P uptake than Itagunmodi and Majeroku soils. Triple super phosphate (TSP) and no P supported higher grain weights and P uptake than rock phosphate (RP) and single super phosphate (SSP).


Key words: Cowpea, maize, phosphorus fertilization, phosphorus uptake, soil types, southwestern Nigeria.


SSP, Single super phosphate; TSP, triple super phosphate; RP, rock phosphate; WAP, weeks after planting.