2025/06/08 by Ogunlade, M. O., Bello, O. S., Ogundeji, B. A. +1
#Bacteria #Cocoa #Fungi #Physicochemical #Soil
paper · doi:10.82552/njhs.v29i1.72-78
Knowledge of the soil nutrients, associated microbes and the interrelationship that exists between them is essential for enhanced cocoa production in growing countries. Hence, this study examined the physicochemical properties and microbial populations/diversity of soil samples obtained from four randomly selected cocoa plots and their respective adjoining forests in Ajassor, Cross River State, Nigeria. The sand (81.63-85.90%), pH (6.25-6.50), calcium (2.70-4.70cmol/kg), aluminium (0.09-0.26cmol/kg) and base saturation (85.40-86.20%) values were significantly different (P≤0.05) in the cultivated cocoa soils, compared with the adjacent forest (67.80%, 6.10, 2.02cmol/kg, 0.80cmol/kg and 69.10%, respectively), which served as the control. The organic carbon (0.90 – 1.25%) and Effective Cation Exchange Capacity, ECEC (5.12 – 8.27 cmol/kg) values were higher in the cultivated soil than the forest soil samples. There were however no significant difference (P≤0.05) in the values of Nitrogen (0.130 – 0.145%) detected in the samples. Microbial profiles of the cocoa plots and adjacent forest also followed similar trend, with the bacterial populations (3.00 x 107 - 8.15 x 107 cfu/g) having much higher figures than their fungal counterparts (9.0×103 - 2.10×104 sfu/g) in all the samples. Also, strong correlation coefficients r (0.866 – 0.976), (0.641 – 0.828), (0.927 – 0.888), (0.411 - 0.833), 0.668 – 0.777), (0.719 – 0.751), (0.624 – 0.656) and (0.767 – 0.929) existed between the microbial populations and the soil sand, pH, available P, carbon, calcium, magnesium, effective cation exchangeable capacity and base saturation, respectively. Thus, laying credence to the fact that there exists some good nexus between soil nutrients/physicochemical properties and the soil microbial community. Increased microbial population and diversity therefore play key roles in the availability of essential nutrients needed for the use of crop plants on cocoa plantations.