Fungi Diversity on Some Fruits and Biological Control using Two Plants Extracts

Abstract

Fruits play an essential role in human nutrition by contributing the necessary growth factors like essential minerals and vitamins in human daily diet maintaining a good and normal health. But rot diseases caused by fungi cause severe losses of agricultural and horticultural crops every year. This work aimed to study fungi diversity on some fruits and carry out biological control using two plant extracts. A total of 17 infected fruit samples were collected from two local markets, small pieces of infected parts were inoculated on prepared plates of Potato Dextrose Agar. Incubation was done for 7 days and pure cultures were made, and pure isolated fungi were identified according to the recommended references. Ethanolic leaf extracts of Ocimum gratissimum and Moringa oleifera were evaluated for in vitro antifungal activities on Aspergillus and Fusarium species isolated from spoilt tomatoes and banana using the Agar Dilution Method. Eleven different fungi species comprising nine genera were isolated from the 17 fruits collected from the Nkwen and main markets of Bamenda. The fungi were identified as Saccharomyces cerevisiae, Aspergillus niger, Penicillium digitatum, Mucor sp, Fusarium sp, Mucor racemosus, Alternaria alternata, Colletotrichum sp, Nodulisporium sp, Fusarium oxysporum and Aspergillus flavus. There was some diversity in isolation frequency of the fungi from the fruits. Aspergillus, Penicillium, and Fusarium were the most common genera that colonized the fruits, with Aspergillus sp. found to be the most dominant fungi responsible for extensive damage of fruits. Ocimum gratissimum and Moringa oleifera leaf extracts had inhibitory activities on the test fungi. The diversity of the fungi identified in this study could be regarded as the most common causes of post-harvest deterioration of fruits. The findings of this study bring further evidence that Moringa oleifera and Ocimum gratissimum leaves extracts have the potential of becoming powerful and safe alternative means of fungi control on fruits instead of the harmful, expensive, environmentally unfriendly chemical fungicides.