EFFECT OF GROWTH MEDIA ON GROWTH AND NUTRIENT UPTAKE OF COCOA SEEDLING VARIETIES NIGERIA.

Abstract

Cocoa (Theobroma cacao L.) is a vital economic crop that serves as a major source of income for many tropical countries and is the raw material for the global chocolate industry. However, poor seedling vigor due to suboptimal nursery growth media often limits successful establishment and productivity in the field. Hence, this study was carried out to determine the effect of different growth media on the growth and nutrient uptake of cocoa seedling varieties at the Teaching and Research Farm, LadokeAkintola University of Technology, Ogbomoso. Factors considered were of three growth media (topsoil only, topsoil + poultry manure, and topsoil + sawdust), and six cocoa varieties (TC1, TC2, TC3, TC4, TC5, and TC6). The 3 x 6 factorial experiment was arranged in a Completely Randomized Design (CRD) with three replicates. Data on plant height, number of leaves, leaf area, and nutrient uptake (N, P, K, Ca and Mg) were analyzed using ANOVA, and means were separated using Duncan’s Multiple Range Test (DMRT) at 5% significance level. Results revealed that both growth media and variety significantly influenced all measured growth and nutrient parameters, with significant interactions. Across all sampling periods, seedlings grown in TS+PM exhibited superior performance in height, leaf number, leaf area, and nutrient uptake compared with TS and TS+SD. At 12 WAS, seedlings in TS+PM attained the greatest mean height (19.21 cm) and leaf area (40.55 cm²). Among the varieties, TC2 produced the tallest seedlings, whereas TC5 and TC6 recorded the widest leaf area and highest nutrient accumulation (N = 0.94%, P = 4.54%, K = 0.67%, Ca = 0.56%, Mg = 0.41%). The interaction between TS+PM and varieties TC2,  TC5 and TC6 resulted in the most vigorous seedlings. The study concludes that integrating poultry manure with topsoil enhances cocoa seedling growth and nutrient composition.