Effect of Water Regime and Organic Amendment on Agromorphological Parameters of Tomato (Solanum lycopersicum L.) Grown in the Open Field on Gleysol in Diabo Department, Central Côte d’Ivoire

The aim of the study was to improve the productivity of the PADMA 108 F1 tomato grown in the field on gleysol in the off-season by the combined application of a water regime and an organic amendment. The study took place in the off-season (July-August) in 2022 at Yomian-Kouadiokro (7°49N, 5°9W) in the Gbêkê region and Diabo department of central Côte d'Ivoire. The methodology consisted in clearing a hydromorphic fallow (a gleysol) of about 10 years and delimiting microplots in randomized Fisher blocks of 3 replicates. In each replication, 12 microplots of 5m2 were distributed in 3 blocks, each comprising 4 treatments (poultry manure and sawdust composts, NPK12-22-22 fertilizer and the no-fertilizer control). In each microplot, tomato seedlings were transplanted into 10 pots. At transplanting, fertilizers were applied as a basal fertilizer at a rate of 0.5Kg/pack (poultry droppings and sawdust) and 85g/pack of NPK at the foot of the tomato compared with the control. After planting, a regular watering of 60 liters of water was applied to each block using a watering can (10L), subjecting the seedlings to a specific watering regime of 7 waterings/week, 4 waterings/week and 2 waterings/week. The results showed a highly significant specific effect of watering 7 times/week and of the organic amendment (poultry droppings) on the agromorphological parameters with the highest values compared with the other treatments. On the other hand, the best values for tomato agromorphological parameters were obtained with the combined effect of watering 2 times/week with organic amendments (poultry manure compost), NPK 12-22-22 mineral fertilizer and sawdust compost to some extent. In conclusion, this study shows that to improve the productivity of the PADMA 108 F1 tomato in the ecosystem studied in the off-season, a watering regime of 2 waterings per week is appropriate, regardless of the type of treatment applied (organic or mineral fertilizers).