Biocontrol fungal diseases of zucchini (Cucurbita pepo ssp) in Côte d’Ivoire by Pseudomonas fluorescens F19

Abstract

The consumption of vegetables and particularly zucchini (Cucurbita pepo ssp) is subject of nutritional recommendations at the world level. However, like other foodstuffs, zucchini can be subject to many microbial alterations causing poor post-harvest practices that could affect its organoleptic and marketable characteristics. The aim of this study was to highlight the capacity of Pseudomonas fluorescens F19 to inhibit the germs of alteration of zucchini sold in Abidjan city (Côte d’Ivoire), in order to improve their shelf life. A sample of 60 zucchini including 30 spoiled and 30 healthy of the Coucourzelle variety was used for this study. The phenotypic identification of the spoilage germs was carried out on Potato Dextrose Agar medium and the inhibition of P. fluorescens F19 was demonstrated in vitro and in vivo. Six species of fungi belonging to three genera (Aspergillus sp., Phytophtora sp., Candida sp.) were isolated from the altered zucchini. Among these spoilage agents, three species including Phytophtora sp, Candida sp and Aspergillus sp (c) showed significant spoilage of zucchini. Phytophtora sp is the main spoilage agent of zucchini with a total spoilage within three days. However, the in vitro biological activity of the supernatant of P. fluorescens F19 showed a significant inhibition of the growth of the fungi responsible of zucchini spoilage with an average of 73.33%. In vivo the use of P. fluorescens F19 allowed to extend the shelf life of Coucourzelle zucchini from 3 to 10 days. P. fluorescens F19 has antifungal properties.