Comparison of genotypic and phenotypic techniques for assessing the variability of the fungus Epicoccum nigrum

Aims: The diversity within a collection of worldwide isolates of Epicoccum nigrum has been studied using several phenotypic approaches. In addition, the abilities of phenotypic and genotypic techniques for the differentiation of a set of isolates are compared. Methods and Results: The methodology used include the study of isozymes (acetyl esterase and alkaline phosphatase), HPLC profile of metabolites and antibiotic activities against a panel of bacteria, yeasts and filamentous fungi, and cytotoxicity against three mammalian cell lines. Two procedures for assessing the relationships within a collection of isolates, using a combination of the techniques, were evaluated, comparing the advantages and disadvantages of each method. Conclusions: The results showed that each individual technique allows differentiation of the isolates studied to some degree and that the information provided by each technique could be considered as complementary. Genotypic techniques were more powerful than the phenotypic ones to discriminate among the strains. Significance and Impact of the Study: This work evaluates the predictive value of several phenotypic techniques on a collection of fungal isolates, and compares the results obtained with genotypic techniques performed on the same strains.