Molecular characterization of Auricularia spp from south-western Nigeria using Random Amplified Polymorphic DNA (RAPD) markers

Abstract

This study was conducted to investigate the genetic diversity in 48 samples of Auricularia species randomly collected from secondary forests in Osun (11), Oyo (10), Ondo (9), Ekiti (8), Ogun (8) and Lagos States (8) of Nigeria. Fourteen Random Amplified Polymorphic DNA (RAPD) markers were used for molecular characterization of Auricularia species. Phylogenetic relations were determined by cluster analysis and Polymorphic Information Content (PIC) and gene diversity determined using standard procedures. The Auricularia species were grouped into 6 distinct clusters based on morphological traits. The PIC value ranged from 0.5594 (OPH-15) to 0.7819 (OPB-12) and gene diversity from 0.5930 (OPH-15) to 0.7977 (OPB-12). Primer OPB-12 was the most informative for genetic diversity of Auricularia species. However, primer OPB-21 gave the highest number of alleles while OPB-12 showed the highest range of gene diversity and accounted for the diversity of the Auricularia species. The dendrogram and the principal coordinate analysis exhibited similar clustered patterns, revealing that all the tested strains could be divided into six distinct groups, each of which correlated with different geographical regions. Molecular characterisation is essential in genetic diversity studies and has proven useful in the classification of Auricularia spp.

Keywords:  Auricularia spp, Cluster analysis, Genetic diversity, Mushroom cultivation, Principal coordinate analysis, Polymorphic information content, RAPD markers