title: Development of a specific TaqMan real-time PCR assay for quantification of Fusarium graminearum clade 7 and comparison of fungal biomass determined by PCR with deoxynivalenol content in wheat and barley.
abstract: A Fusarium graminearum clade 7 specific real-time quantitative PCR (qPCR) assay was developed in this study based on unique polymorphisms in sequences of the mating type protein (MAT) gene. PCR amplification was not observed in eight phylogenetic lineages of the F. graminearum complex and four other closely related Fusarium species. Accuracy of the quantification of the real-time PCR assay was verified with wheat DNA spiked with F. graminearum clade 7 DNA. Wheat samples representing two Canadian wheat classes, CWRS (Canadian Western Red Spring) and CWRW (Canadian Western Red Winter) were used to determine the relationships among F. graminearum DNA, deoxynivalenol (DON) and Fusarium damaged kernel (FDK). The amount of DON and F. graminearum DNA remaining after removal of FDK varied among samples, but was sometimes substantial. Positive correlations were observed between F. graminearum clade 7 DNA (in picograms) and DON as well as FDK. There was also a strong correlation between FDK and DON in CWRS and CWRW wheat composite samples, but the inherent variability in individual producer samples precluded a definitive correlation. For barley, a positive correlation was observed between Fusarium DNA and DON values. Real-time PCR assays can be a valuable tool for barley as there are no reliable symptoms to visually assess the level of Fusarium head blight in this crop.
authors.affiliation: Canadian Grain Commission, Winnipeg, Manitoba, Canada. tigst.demeke@grainscanada.gc.ca
authors.forename: Tigst
authors.initials: T
authors.lastname: Demeke
authors.forename: Tom
authors.initials: T
authors.lastname: Gräfenhan
authors.forename: Randy M
authors.initials: RM
authors.lastname: Clear
authors.forename: Anh
authors.initials: A
authors.lastname: Phan
authors.forename: Indira
authors.initials: I
authors.lastname: Ratnayaka
authors.forename: Julie
authors.initials: J
authors.lastname: Chapados
authors.forename: Susan K
authors.initials: SK
authors.lastname: Patrick
authors.forename: Don
authors.initials: D
authors.lastname: Gaba
authors.forename: C André
authors.initials: CA
authors.lastname: Lévesque
authors.forename: Keith A
authors.initials: KA
authors.lastname: Seifert
mesh_terms: D001483:Base Sequence; D018533:Biomass; D004271:DNA, Fungal / Q000032:analysis*; D005656:Fungal Proteins / Q000235:genetics; D005670:Fusarium / Q000235:genetics*; D005838:Genotype; D001467:Hordeum / Q000382:microbiology*; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology*; D016133:Polymerase Chain Reaction / Q000379:methods*; D011110:Polymorphism, Genetic; D015203:Reproducibility of Results; D012639:Seeds / Q000382:microbiology; D017422:Sequence Analysis, DNA / Q000379:methods; D014255:Trichothecenes / Q000032:analysis*; D014908:Triticum / Q000382:microbiology*
chemical_list: D004271:DNA, Fungal; D005656:Fungal Proteins; D014255:Trichothecenes; C007262:deoxynivalenol