Effect of Inorganic Fertilizer Application on Growth and Yield of Thevetia peruviana (Pers) Schum. (Yellow Oleander) in the Southern Guinea Savannah of Nigeria

Abstract

Growth and yield parameters of Thevetia peruviana (Pers) Schum. were evaluated under in-organic fertilizer in 2009, 2010 and 2011 rainy seasons at the Research farms of the Biofuel and Alternate Renewable Energy Ltd, Edidi, Kwara State in the southern Guinea savannah of Nigeria. The objective of the study was to determine the influence of different rates of N and P fertilizers on the vegetative growth and yield of T. peruviana. The experiment was laid out in a RCBD in a factorial arrangement with three replications. The factors includes: 3 levels of N (0, 30 and 60 kg ha^-1) and 3 levels of P (0, 30 and 60kg ha^-1) which were combined factorially. The results indicated that application of 0 kg N ha^-1 and 30 kg P₂O₅ ha^-1 resulted in increased plant height, number of primary branches, stem girth, number and weight of harvested seeds. It was also observed that application of 60 N kg ha^-1 and 0 kg P₂O₅ kg ha^-1 delayed number of days to both first and 50% flowering. Based on the result of this study it is recommended to apply only 30 kg P₂O₅ ha^-1 because the native nitrogen in the soil was enough for both the growth and yield performance of T. peruviana in the study area.

Keywords:  Thevetia periviana, Growth, Yield, Nitrogen and Phosphorus fertilizers.