Abstract

Field experiments were carried out to assess the impact of 100% NPK fertilizer recommendation (300 kg NPK 20:10:10), 100% Tithonia compost (TC), 75% NPK + 25% TC, 50% NPK + 50% TC, 25% NPK + 75% TC and control (non-fertilized plant) on the growth, fruit yield, nutritional and lycopene contents of three tomato varieties (Raoma VF; Ogbomoso local and Califonia wonder). The experiment was a split plot fitted into a randomized complete block design replicated three times. Data were collected on growth and reproductive parameters, fruit and seed attributes, and fruit proximate and nutritional contents. Data collected were subjected to analysis of variance to determine significant means. Significant varietal differences were observed among the tomato varieties in terms of growth, fruit yield and nutritional attributes. The plant dry matter yield was highest in Ogbomoso local and least in Roma VF. Fruit yield obtained with Ogbomoso local was 45 and 56% higher than what was obtained for Roma VF and Califonia wonder, respectively. In terms of vitamin C content, Roma VF fertilized with 50% NPK + 50% TC gave the highest value which is 23 to 67% higher than values obtained from the other treatment combinations. Again, irrespective of variety, organically grown tomato contains higher content of lycopene. It was also observed that the higher the proportion of TC compost in the treatments, the better the lycopene content. It could be concluded that the use of organic fertilizer has potential in improving the growth, fruit yield and nutritional contents of any of the three tomato varieties studied.

Key words: Lycopersicon esculentum, compost, inorganic fertilizers, fruit yield, nutritional quality, lycopene content.

Abbreviation

TC, Tithonia compost; WAT, week after transplanting; TSS, total soluble solid.