Effect of Periods of Field Establishment and Irrigation on Growth and Yield Performance of Thevetia peruviana (Pers.) Schum

Two irrigation regimes on the growth and yield performance of Thevetia peruviana (Pers) Schum were evaluated during the 2010 and 2011 rainy seasons. The study was carried out at the Research Farms of the Bio-fuel and Alternate Renewable Energy Ltd, Edidi, Kwara State in the southern Guinea savannah of Nigeria. Mature seeds were sown in March and May of both years and transplanted in May (early) and July (late) respectively. During each of the field establishments, early and late of the two years, the treatments consisted of two irrigation regimes (irrigated and non irrigated) and one plant population (2,500 plants ha-1), laid out in Randomised Complete Block Design with four replicates. Application of irrigation significantly increased plant height, number of primary branches, stem girth, number of harvested seeds, weight of harvested seeds, seed length, seed diameter but delayed number of days to first and 50% flower appearance at late period of field establishment while the effect of irrigation regimes was not significant on these parameters at early period of field establishment. The plants should therefore be irrigated during the dry season if the field establishment was done late (around July and August) to improve the vegetative growth and yield performance but if transplanting was done early (around May) irrigation may not be necessary. Early field establishment is therefore recommended