Aims: To develop a PCR-based method for quantitative detection of Fusarium asiaticum (Fa) and Fusarium graminearum (Fg) in wheat seeds.
Methods and results: Based on the sequences of the cyp51A gene, two primer pairs FaF + FaR and FgF + FgR were developed for the species-specific detection of Fa and Fg, respectively. To simultaneously detect these two phylogenetic species, a pair of primers FgaF + FgaR was developed based on the first and the second introns of beta-tubulin gene. This primer pair amplified a 228-bp fragment only from Fa and Fg isolates, but not from 22 other Fusarium spp. and 13 other fungal species. A real-time PCR with this primer pair was able to quantify minute amounts of Fa and Fg DNA in wheat seeds rapidly.
Conclusions: PCR primers designed based on the sequence of cyp51A or intron region of beta-tubulin gene could allow differentiation of genetically related fungal species.
Significance and impact of the study: The sensitive and quantitative detection method can be readily used in epidemiological studies and in assessing risk of Fusarium mycotoxin contamination in wheat samples.