Molecular characterisation of fungi from Arachis hypogaea

Abstract

Arachis hypogaea L. (groundnut) is a food and oil crop of global interest. Groundnut seeds are plagued by fungal organisms especially during storage. This reduces the quantity and the commercial value of the products. Molecular techniques for determining the species of a fungus based on the PCR amplification and sequencing of the Internal Transcribed Spacer (ITS) region of the fungus has proven to be a more reliable method of identifying fungal species. This study was carried out to isolate and identify the fungi associated with groundnut seeds using both traditional cultural techniques and molecular method. Fungi were isolated from diseased groundnut seeds obtained from Choba market, Port Harcourt, using both Standard Blotter and Potato Dextrose Agar methods. DNA was extracted using Zymo Fungal/Bacteria DNA Miniprep Kit and was amplified using universal primer pair; 27F and 1525R. PCR products of 236 and 615 base pairs were sequenced and the fungal isolates were identified as Lasiodiplodia theobromae and Aspergillus penicillioides, respectively. This study has provided information on the fungal species associated with A. hypogaea which will help in suggesting ways to reduce the incidence of these organisms. Phylogenetic analysis showed the relationship that exists between the fungal isolates and other closely-related species in Genebank such as Pediastrum duplex, Penicillium penicillioides, Colletotrichum capsici and Lasiodiplodia pseudotheobromae.