Giberella fujikuroi species complex isolated from maize and wheat in Iran: distribution, molecular identification and fumonisin B1in vitro biosynthesis

Abstract BACKGROUND Contamination of food and agricultural crops by Fusarium species is a major concern of food spoilage and a potential public health hazard. In the present study, natural contamination of maize and wheat samples from main cultivation areas of Iran by Fusarium species belonging to the Giberella fujikuroi species complex was evaluated, with special attention to the ability of the isolates to produce fumonisin B 1 ( FB 1 ). RESULTS A total of 55 Fusarium isolates were obtained from 27/32 maize samples (84.4%) and 11/15 wheat samples (73.3%). They were identified as F. verticillioides (47.3%), F. proliferatum (47.3%), F. fujikuroi (1.8%), F. nygamai (1.8%) and F. redolens (1.8%) by sequence analysis of translation elongation factor 1‐ α ( TEF1 ‐ α ). Twenty‐two of 55 Fusarium isolates belonging to F. proliferatum (23.6%), F. verticillioides (14.5%) and F. fujikuroi (1.8%) produced FB 1 in the concentration range 230.4–9565.0 µg mL −1 . The dendrogram resulting from the TEF1 ‐ α profile showed that the genotypes were divided into clusters I, II and III , of which cluster III contained only F. redolens , its first report from Iran. CONCLUSION On the basis of in vitro FB 1 biosynthesis of the analyzed strains, the high degree of contamination of maize and wheat with Fusarium strains reported here should be considered as a potential public health threat, because a meaningful number of the isolates were found to produce hazardous levels of carcinogenic FB 1 . © 2015 Society of Chemical Industry