_____________________________________________________________________________________________________ *Corresponding author: E-mail: ptropala@yahoo.com; International Journal of Plant & Soil Science 6(2): 64-72, 2015; Article no.IJPSS.2015.097 ISSN: 2320-7035 SCIENCEDOMAIN international www.sciencedomain.org Effect of Sources of Phosphorus on Phosphorus Sorption in Cambisols and Ferralsols of Western Kenya Peter A. Opala 1* 1 Department of Soil Science, Maseno University, P.O.Box, Private Bag, Maseno, Kenya. Author’s contribution This whole work was carried out by author PAO. Article Information DOI: 10.9734/IJPSS/2015/9215 Editor(s): (1) Sławomir Borek, Department of Plant Physiology, Adam Mickiewicz University, Poland. (2) Sunday Obalum, Department of Soil Science, University of Nigeria, Nigeria. Reviewers: (1) Atilgan Atilgan, Suleyman Demirel University, Faculty of Agriculture, Department of Agricultural Structures and Irrigation, Turkey. (2) Bocar Ahamadou, Agricultural Sciences & Techniques, Rural Polytechnic Institute for Training & Applied Research , IPR/IFRA of Katibougou, Mali. (3) Anonymous, Iran. Complete Peer review History: http://www.sciencedomain.org/review-history.php?iid=954&id=24&aid=8015 Received 28 th January 2014 Accepted 8 th April 2014 Published 2 nd February 2015 ABSTRACT The influence of two organic materials (OMs); Tithonia and FYM and inorganic materials; triple superphosphate (TSP) and Minjingu phosphate rock (MPR) and Busumbu phosphate rock (BPR), when applied alone or in combination, on P sorption at two sites, Kakamega and Bukura, in western Kenya was investigated. The soil at Bukura was a Ferralsol while that at Kakamega was a Cambisol. A randomized complete block design with 3 replications was used. All the P inputs were uniformly broadcast on the plots and then incorporated into the top soil (0-15 cm) in April 2007. Soils were sampled at 4 and 9 weeks after incorporation of phosphorus inputs (WAI) from each of the treatments and the soil P sorption characteristics determined. The equilibrium P concentration which represents the amount of P in the equilibrium solution at zero P sorbed was < 0.2 mg P L - 1 regardless of the input combination used. The P sorption capacity of the soil at Kakamega was low compared to that at Bukura and was generally not affected by the treatments. None of the P sources significantly reduced the amount of P sorbed at Kakamega. However at Bukura, the amount of P sorbed (q) was significantly lower than the control for only Tithonia when applied alone and FYM applied in combination with TSP at 4 and 9 WAI. Tithonia applied with TSP Original Research Article