Tomato yield and economic performance under organic and mineral fertilizer applications in coastal Togo

Research efforts towards enhancing vegetables production are still needed in Togo. We assessed tomato (Solanum lycopersicum) yield and associated economic returns under three soil fertility management strategies in a 3-yr study. Three tomato varieties were used including: MONGAL-F1 (V1), SUMO-F1 (V2) and COBRA 26-F1 (V3). The fertilization regimes were: no fertilizer application as the control (F1), application of 200 kg of N15P15K15 + 100 kg of urea (46% N) corresponding to N76P30K30 ha-1 (F2) and application of farm yard manure (FYM) at the rate of 6 Mg ha-1 (F3). The 3-yr period was segmented into two cropping periods with three tomato crops each. Tomato fresh fruit yields were collected and were used to determine the net cash return through a partial budget analysis under each variety – fertilization regime combination. Across tomato varieties, three-crop mean yields were 93 to131% and 109 to 144% higher for fertilization regimes F2 and F3, respectively, as compared to yield under the control (F1), and mean yields with F3 were 7.5% on average superior to those for F2. Irrespective of fertilization regime, the MONGAL-F1 mean yields were 6 to 24 and 16 to 31% superior to yields under SUMO-F1 and COBRA 26-F1, respectively, and SUMO-F1 based yields were 6 to 10% higher than those for COBRA 26-F1. Higher economic returns (typically ranging from 11000 to 15500 USD) were recorded when fertilizers were applied, and lower returns (typically in the range of 250 to 3000 USD) were obtained with no fertilization, with the highest economic return under the V1F3 combination during the February to May cropping period.