STORAGE FUNGI OCCURRENCE IN MELON (Citrullus colocynsthis) IN UMUAHIAAND THEIR CONTROL USING SELECTED BOTANICALS

Abstract

Storage fungi cause deterioration of stored melon (Citrullus colocynsthis) kernels, leading to loss of quality and quantity of produce. This study was carried out to identify the fungal pathogens associated with postharvest storage rot of C. colocynsthis kernel and to evaluate the efficacy of antifungal potentials of Piper guineense, Xylopia aethiopica and a combination of both (Piper + Xylopia) in the control of rot-causing pathogens. Isolation and identification of fungi were done using standard laboratory procedures. Hand and machine-peeled egusi samples (n=12) were collected from Ubani and Orie-ugha markets. Experimental design was completely randomized design with three replicates. Data were analyzed using anlysis of variance at á Rhizopus sp; 0.05. Penicillum sp, Aspergillus niger, A. flavus, A. terreus and A. fumigatus were encountered in C. colocynsthis kernels. Aspergillus flavus, A. niger and Rhizopus sp were most prevalent and highly pathogenic species. Machine-peeled egusi kernels had higher 20.70% mould content than the hand-peeled < 14.00%. Botanical treatments had significant (p=0.05) effect on fungi growth in-vitro and in-vivo. Aspergillus flavus growth inhibition ranged from 37.84-100.00%, A. niger 65.47-100.00% and Rhizopus sp 27-94% across incubation period in in-vitro trial. For in-vivo trial, X. aethiopica inhibited A. flavus growth by 0.00 and 3.33 A. niger by 40 and 66.67%, Rhizopus by 50.00 and 66.67% before and after treatment respectively. Piper guineense reduced A. flavus growth by 63.33% and 13.33%, A. niger by 68.89% and 84.44%; Rhizopus sp by 90.00% and 63.33% before and after treatments, respectively. Xylopia + Piper treatment reduced A. niger by 48.89% and 84.44% before and after treatment, respectively; while Rhizopus sp growth was reduced by 70.00% before and after treatment. Botanicals particularly Piper guineense consistently reduced fungi growth considerably and could be exploited in the management of storage fungi of egusi kernels.