EFFECTS OF NUTRIENT SOURCES ON FRUIT LYCOPENE AND SELECTED PHYTOCHEMICALS OF TOMATO (Solanum lycopersicum L.) IN OGBOMOSO, NIGERIA

Abstract

Tomato (Solanum lycopersicum L.) is a globally important vegetable crop valued for its nutritional and health-promoting properties, particularly its lycopene content. However, tomato fruit quality in Nigeria remains constrained by declining soil fertility and suboptimal nutrient management practices. This study evaluated the effects of different nutrient sources on fruit lycopene and selected phytochemicals of two tomato varieties (Roma VF and UC82B) in Ogbomoso, Nigeria. A field experiment was conducted at the Teaching and Research Farm, Ladoke Akintola University of Technology, Ogbomoso, Nigeria. The experiment was a 2 × 6 factorial combination in a Randomized Complete Block Design with three replications. The treatments were two tomato varieties (Roma VF and UC82B) and six fertilizer treatments: Control, 100% NPK (20-10-10), 100% Tithonia compost (10 t/ha), Supergro foliar fertilizer (1 L/ha), 50% NPK + 50% Compost, and 25% NPK + 75% Compost. Data were collected on proximate composition, mineral content, vitamin content, and lycopene content. Data were subjected to analysis of variance using SAS version 9.4 and means were separated using Duncan's Multiple Range Test at 5% probability level. For proximate composition, UC82B outperformed Roma VF across all parameters, recording crude protein (1.790%), crude fibre (0.694%), fat (0.245%), ash (0.354%), and moisture (87.858%). Foliar application consistently produced the highest crude protein (1.897%), crude fibre (0.742%), fat (0.283%), ash (0.415%), and moisture (87.858%). For vitamins, UC82B had vitamin C (40.728 mg/100g) and vitamin A (0.926 mg/100g), while foliar application produced the highest vitamin C (46.228 mg/100g) and vitamin A (1.020 mg/100g). Lycopene content was not significantly different between varieties. However, foliar fertilizer produced significantly higher lycopene (22.22 mg/100g) than the control (11.29 mg/100g). For farmers prioritizing nutritional quality and high lycopene content, UC82B variety with foliar application of Supergro (1 L/ha) is recommended in the study area.