Tomato yield optimization using fertilizer sources and sowing dates in Okitipupa, Southwest Nigeria

Abstract

Tomato (Solanum lycopersicum L.) productivity in rainforest agroecology is limited by climatic conditions, soil nutrient management, and sowing windows. Thus, a rainfed experiment was conducted to evaluate the effects of nutrient sources and sowing dates (SD) on the growth and yield of tomato varieties in Okitipupa, in 2022–2023. A split-plot experiment; 4NS (10 t/ha organomineral fertilizer - OMF, 15 t/ha organic fertilizer - ORF, and 300 kg/ha NPK) and tomato varieties ('Platino', 'Ibadan Local', 'Beske', and 'Roma') sown on 4 SD (19 May, 29 May, 8 June, and 18 June) were arranged in a RCBD replicated thrice, at T&R Farm of Olusegun Agagu University of Science and Technology. Growth, yield, and yield metrics were collected. The results revealed significant interactions: 'Platino' treated with OMF achieved the tallest plants (126.19 cm), 'Ibadan Local' produced the highest leaf number (610/plant) and branches (28.81/plant). 'Platino' and 'Ibadan Local' varieties, treated with ORF, yielded the highest fruit weight, 696.2 g and 638.80 g, respectively, and a superior harvested yield of 3946.5 kg/ha and 3452.80 kg/ha, respectively. Conversely, 'Roma' under control conditions recorded the lowest fruit weight (1196.5 kg/ha). SD significantly influenced yield attributes. 18-June SD extends the anthesis days but produced the highest fruit number and weight. Furthermore, growth and yield-contributing attributes were positively correlated with soil nitrogen levels. The OMF proved to be the most effective in enhancing soil fertility and tomato performance. 'Platino' and 'Ibadan Local' varieties demonstrated optimal adaptation and yield potential. Given the prevailing environmental conditions, SD 18-June emerged as the most suitable for maximizing tomato productivity in this region.