Mineral Fertilizers from Soil Diagnosis Reduce the Decomposition Time of Cocoa Leaf Litter in the South-Western of Cote d'ivoire

Abstract

A study on soil mineral fertilization was carried out over three years in three cocoa farms in the Nawa region of south-western Côte d'Ivoire. The aim of this study was to evaluate the effects of mineral fertilizers on the decomposition time of cocoa leaf litter. The experimental design was Fisher block with four treatments (T0, T1, T2, T3) repeated three times. The treatments were for T0, the control without fertilizer, for T1, NPK fertilizer 0-23-19, for T2, NPK fertilizer 0-15-15 + 17 CaO + 5 MgO + 1 B2O3 + 0.5 Zn and for T3, NPK fertilizer 4-10-10 + 19 CaO + 4 MgO + 0.8 B2O3 + 0.3 Zn. In each treatment, 3 plots of 1 m2 were delimited with a 1 cm2 mesh wire grid. The rate of decomposition of the cocoa leaf litter was made by measuring twice a year the weight loss of the ground litter contained in the plots. Comparison of the average decomposition rates between treatments showed that the fertilized soils had the best rates during the first 6 and 12 months of the trial. In Soubré, the T2 treatment (24.6±0.6%) in the 6th month and the T1 (72.6±6.6), T2 (82.4±1.6) and T3 (78.8±4.0%) treatments in the 12th month had the best decomposition rates. At Divo, treatment T1 (38.8±0.5%) in month 6 and treatments T1 (57.8±1.7%), T2 (67.9±10%) and T3 (66.9±7.7%) in month 12 were the best. At Méagui, decay rates did not differ between treatments throughout the trial. The application of mineral fertilizers resulting from soil diagnosis reduced the decomposition time of the cocoa leaf litter.