GROWTH RATES OF PARKIA biglobosa JACQ. SEEDLINGS (AFRICAN LOCUST BEAN TREE) AS INFLUENCED BY TWO INORGANIC MANURES

Abstract

One of the prominent fruit trees in the savanna ecosystem is Parkia biglobosa Jacq. (African Locust Bean Tree). Apart from being a nitrogen fixing tree, the seeds from its matured pods are often processed and used as soup condiment in some African countries most especially Nigeria. The population density of this plant species is low, its growth rate is slow and the processed seeds are not abundantly available and therefore costly. Thus, the influence of two inorganic manures/fertilizers (Urea and N. P. K.) on the growth rate of the seedlings of this species was investigated to pave way for massive production. The experimental design employed was completely randomized design (CRD) comprising 3 treatments and 4 replicates (treatments A (sandy loam + Parkia biglobosa seeds + N.P.K), B (sandy loam + Parkia biglobosa seeds + Urea) and C (sandy loam + Parkia biglobosa seeds as control). Seedlings’ emergence rates/percentages and morphological growth indices /parameters (plant height, leaf count, number of branches, collar girth and leaf area) were evaluated. Application of inorganic manures commenced at the 6th week after germination/seedling emergence. Results from statistical data analyses (SPSS 21.0) indicated significant differences (at P≤0.05) among the treatments. Seedlings in Urea + sandy loam (treatment B) had the highest mean values/fastest growth rate followed by treatment A and treatment C was the least. Incontrovertibly, faster growth rate of this important tree species could be achieved by employing Urea and relatively, N.P.K fertilizer could also be used.