The effects of organic waste on the postharvest fungal attack and disease severity on <i>Irvingia gabonensis</i> kernels

Abstract

The effects of organic waste, orange peels and charcoal on the postharvest fungal attack and disease severity on Irvingia gabonensis kernels stored for six (6) months was investigated. Irvingia gabonensis kernels were treated with orange peels and charcoal and the fungal load and diversity were determined using standard microbiological techniques. The study revealed that the same fungal species which include Aspergillus fumigatus, Aspergillusniger, Aspergillus terreus and Mucorspp were encountered in both treatment and control. Furthermore, it was observed that disease severity in the treatment sample reduced by 50 % on the average. The kernels stored in bags without treatment was discoloured and lost its market value whereas 86-88% of kernels stored in bags with either dried orange peels or charcoal remained in good condition. It was observed that the fungal load which ranged 1 CFU/g - too many to count in the control was significantly higher than those stored in bottles with treatment (1-3CFU/g). In orange peel treated kernels Aspergillus fumigatus was the most occurring fungal isolate (3 CFU/g). Aspergillus fumigatus and Mucor spp. were the most occurring in charcoal treated kernels with 2 CFU/g. while Mucor spp. was the most occurring (25 CFU/g) in the control, closely followed by Aspergillus fumigatus (14 CFU/g). Orange peels and charcoal were effective in reducing fungal spoilage of kernels and would prove useful in reducing postharvest loss.