Author
VILLANI, A - National Research Council - Italy | |
Proctor, Robert | |
McCormick, Susan | |
Brown, Daren | |
MORETTI, A - National Research Council - Italy | |
LOGRIECO, A - National Research Council - Italy | |
SUSCA, A - National Research Council - Italy |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 4/6/2016 Publication Date: 4/6/2016 Citation: Villani, A., Proctor, R., McCormick, S.P., Brown, D.W., Moretti, A., Logrieco, A.F., Susca, A. 2016. Genetic variability in cereal isolates of the Fusarium incarnatum-equiseti species complex [abstract]. Interpretive Summary: Technical Abstract: The F. incarnatum-equiseti species complex (FIESC) includes fungi associated with diseases of multiple agricultural crops. Although members of FIESC are considered moderately aggressive, they produce diverse mycotoxins, including trichothecenes. Because FIESC exhibits cryptic speciation, DNA-based phylogenetic analyses are required to identify some species. Here, we used EF-1a, RPB2, CaM, and TUB2 gene sequences to examine phylogenetic relationships of 69 isolates with FIESC-like morphology recovered from cereals in the EU and North America. In the resulting phylogeny, the majority of isolates were resolved into 4 previously described phylogenetic species of FIESC, and 7 isolates were resolved into a clade that likely constitutes a novel species (FIESC 31). Comparisons of 12 genomes, representing FIESC 31 and 11 previously described FIESC lineages, revealed marked variation in distribution of mycotoxin biosynthetic gene clusters. The trichothecene cluster was present in all 12 genomes, but differed in presence, absence and arrangement of genes relative to the cluster in the F. sambucinum species complex (FSAMSC), the other major lineage of trichothecene-producing fusaria. Notably, the FIESC clusters includes a transcription factor gene that is absent in the FSAMSC cluster. These results indicate that at least 5 FIESC species occur on cereals, and although the species vary in genetic potential to produce several mycotoxins, their potential to produce trichothecenes is uniform. |