Biocontrol of Post-harvest Fungal Diseases of Pineapple (Ananas comosus L.) Using Bacterial Biopesticides

Abstract

Pineapple (Ananas comosus L.) is a monocotyledon, herbaceous, of the Bromeliad family. Cote d’Ivoire is the leading supplier of fresh pineapple to the European market. For reasons of sanitary quality and also due to the deterioration under the action of several factors of the marketable quality of the fruits, pineapple suffers a slump in the European market. To deal with the problem linked to the deterioration of fruits under the action of microorganisms, phytosanitary products are used. However, these foods present risks for consumers and may be responsible for public health problems. The objective of the present study is to reduce post-harvest losses of pineapple fruit due to fungal contaminants using bacterial biopesticides such as Bacillus subtilis GA1, Pseudomonas fluorescens F19 and Pseudomonas fluorescens CI. To this end, isolations followed by identification by PCR-ITS-RFLP of the fungal strains carried out on 200 samples composed of healthy and altered pineapple fruits in order to determine the main fungal strains responsible for their alteration have been made. The antifungal activity of biopesticides has been tested in vitro and in vivo to assess the potential for inhibition against isolated fungal strains. The results indicate that 5 fungal genera namely Rhizopus, Geotrichum, Neurospora, Candida and Aspergillus were isolated. Antagonist tests using all three biopesticides reduced spoilage. This study contributed to the development of biopesticides in the fight against fruit spoilage fungi in Cote d'Ivoire.