Occurrence of post-harvest fungi affecting sweetpotato (Ipomoae batatas (L) Lam) in Ebonyi State, South Eastern Nigeria
Postharvest fungal spoilage is one of the major constraints to sweetpotato production. The study investigated the occurrence of the spoilage fungi affecting sweetpotato in Ebonyi State. Rotten sweetpotato roots (100 each in dry and rainy seasons) and healthy roots were collected from Ebonyi State for laboratory analysis. From the rotten sweetpotato specimens, fungi were isolated and characterized using morphological properties and confirmation via Partial ITS rDNA Sequencing Analysis and a BLAST Search with the GenBank Sequence. Isolates’ pathogenicity was tested on healthy sweetpotato roots. Data was subjected to frequencies and percentages. Three hundred and fifty-two isolates were obtained from 200 sweetpotato samples. Five distinct genera and 7species of fungi were identified and the later included Rhizopus oryzae, Aspergillus flavus Fusarium solani Aspergillus awamori, Aspergillus niger, Penicillium expansum and Botrydiplodiae theobromae. The frequency of occurrence of the fungi species varied with respect to pathogen and season of isolation. Botryodplodia theobromae was the most frequently isolated fungi, followed by R. oryzae, A. niger, A. flavus, F. solani. P. expansum and A. awamori. The percentage occurrence of fungi isolation was both qualitatively and quantitatively higher in the dry season than in the rainy season. All the isolated fungal species were confirmed positive to pathogenicity test and two major categories of rot were predominantly incited by the fungi. The need to initiate fungi rot control is emphasized. There is therefore need to encourage the farmers to mitigate root fungi infection and give the issue of storage equal attention as yield improvement if the quality of their harvested produce is to be maintained and postharvest losses reduced.
Keywords: Ebonyi State, Occurrence, Postharvest Fungi, Rot, and Sweetpotato