Effects of organic fertilizer (NPK 5-9-19) and mineral (NPK 12-11-18) on soil chemical properties in tomato crop in the South and Mid-west of the Ivory Coast

A study on mineral and organic liquid fertilizer was carried out in the South and Central West of Ivory Coast during a period of two years in order to improve soil fertility in tomato crop. More specifically, it evaluated the effects of 4 doses of organic fertilizer (NPK 5-9-19), associated or not with mineral fertilizer (NPK 12-11-18) on the content of soil organic matter, C/N ratio, the sum of exchangeable bases, available phosphorus, CEC and pH. The experimental design was a split-plot, with four repetitions with mineral fertilizer as the primary factor, and organic fertilizer as secondary factor, at 4 doses (Lha-1): C0 = 0 (control), C1 = 2 5; C2 = C3 = 3.75; and 5. The results showed that 3.75 Lha-1 of fertilizer organic (NPK 5-9-19), associated with the low dose of mineral fertilizer (NPK 12-11-18) had the best positive impact on organic matter, sum of exchangeable bases, and available soil phosphorus. The treatment with 3.75 Lha-1 of organic fertilizer alone increased more CEC and soil pH while the contributions of 2.5 and 3.75 Lha-1 had the advantage of increased C/N ratio of the soil.