Effects of a municipal solid waste compost and mineral fertilization on plant growth in two tropical agricultural soils of Mali

A pot experiment was conducted to compare the effects of compost and mineral fertilization on the growth and chemical composition of ryegrass (Lolium perenne L.) in two Malian agricultural soils (Baguinéda, abbreviated as Bgda, 12°23′ S, 7°45′ W and Gao, 16°18′ N, 0° GM). Treatments included: control, NPK alone, NPK+C25, NPK+C50, NPK+C100, PK+C50, NK+C50, NP+C50, K+C50, P+C50, N+C50 and C50 alone, where NPK represents the non-modified Hoagland’s solution (corresponding to 271, 95 and 172 kg/ha of N, P and K respectively) and C25, C50 and C100 the different rates (25, 50 and 100 T/ha) of compost. Compost and mineral fertilization significantly increased dry matter production. The application of 50 T/ha of compost alone increased the dry matter yield by 10% and 17.5% while mineral NPK alone, by 69.7% and 65% for Gao and Bgda soils, respectively. The combination of compost and mineral NPK (NPK+C25 for Gao and NPK+C50 for Bgda) showed the highest crop yields. Increases in soil organic carbon, available P, Fe, Mn, Zn, Cu, K and pH were observed in treatments with compost. Therefore, compost appeared to be a good supplier of nutrients for tropical soils.