IN VITRO EFFICACY OF SOME BOTANICAL EXTRACTS AGAINST Fusarium oxysporum ASSOCIATED WITH POST HARVEST LOSSES OF TOMATO (Solanum lycopersicum L.) AT SELECTED LOCATIONS IN KANO STATE

Abstract

As an important vegetable crop in Nigeria, demand for fresh tomato is high for both domestic use, eateries, and markets. However, post-harvest losses are threat to harvested tomatoes. This study aimed to isolate, identify fungal pathogens associated with post-harvest spoilage of tomato, as well as to evaluate the efficacy of some aqueous plant extracts against these post-harvest fungal pathogens. Also to identify influence of cultivars planted on post-harvest losses of tomatoes. In this study, fungi associated with the post-harvest spoilage of tomato were identified as Fusarium oxysporum, Aspergillus niger, Rhizopous stolonifer. Efficacy of aqueous plant extracts at different concentration (100%, 75%, 50%, 0%, check) against mycelial growth of the above pathogens were evaluated, results showed eucalyptus leaves extract, chili pepper and olive leaves extracts significantly inhibited mycelial growth of the tested fungi and Fusarium oxysporum was the most inhibited pathogen. The data from this work show that chili pepper extract was found as most effective aqueous extract inhibiting growth of all the fungi, even at low concentration compared to other extracts. For the in vivo experiment, all the plant extracts where found to be effective in controlling F. oxysporum associated with post-harvest spoilage of tomato, but the efficacy vary between plant extracts, and also with concentrations, 100% concentration is the most effective concentration. The level of susceptibility of fruit tomato to F. oxysporum was found to vary with the cultivars. This proved that, plant extracts have the potential to serve as an alternative for developing bio-pesticides for the management of tomato rots because they are easily available, affordable and environment friendly.