MATERIALS AND METHODS
A factorial experiment comprising two factors, Fertilization (4 levels) and Genotypes (5 types) arranged in a Randomized Complete Block Design (RCBD) with 3 replications was used. The trial was installed at the Council for Scientific and Industrial Research (CSIR)-Crops Research Institute, Fumesua, near Ejisu-Kumasi (6043’00’N and 1028’0”W), Ghana. Two trials were conducted from 9th September 2007 to 17th September 2008 and 22nd May 2009 to 22nd July 2010. The four fertilizer rates were (viz F0: 0 N – 0 P2O5 – 0 K2O kg/ha(Control), F1: 60N – 30 P2O5 – 90 K2O kg/ha - Low, F2: 120N – 60 P2O5 – 180 K2O kg/ha - Medium and F3: 180N – 90 P2O5 – 270 K2O kg/ha – High) were applied to the following 5 genotypes: Debor (G1), Afisiafi (G 2), Tuaka (G3), Afebankye (G4) and Sisipe (G5). Bankye wura (23 – 17 - 16) a fertilizer formulated by WIENCO Ghana Limited was used as basal and top dressed with Urea, Triple Superphosphate and Muriate of potash. A plot size measuring 5.0 m x 4.0m was adopted for each treatment. First fertilizer application was done at 5 weeks after planting (WAP) followed by a top dressing at 5 months after planting (MAP). Soils samples were taken from depths of 0 – 20 cm before fertilizer application and also at harvest for routine analysis. Statistical analysis was done using StatView 5.0.1 soft ware.