Trichothecene genotypes, chemotypes and zearalenone

YERKOVICH, N; PALAZZINI J.M; SULYOK M; CHULZE , S.N

TROPICAL PLANT PATHOLOGY

SOC BRASILEIRA FITOPATHOLOGIA

Año: 2017 vol. 42 p. 190 - 196

1982-5676

Members of Fusarium graminearum species complex are the main pathogens associated with Fusarium headblight (FHB) in wheat in Argentina, which produce trichothecene mycotoxins that are found in wheat grain and by-products.  The aim of this study was to determine the chemotype and trichothecene genotypes of Fusarium graminearum species complex strains isolated from wheat in Argentina duringan epidemic and a non-epidemic harvest season. A total of 115and 108 strains obtained from wheat during 2012/13 and2014/15 harvest seasons, respectively, were identified as belonging to the Fusarium graminearum species complex. PCRassays were used to differentiate the 15-acetyldeoxynivalenol (15-ADON), -acetyldeoxynivalenol (3-ADON) andnivalenol (NIV) genotypes. The trichothecene type B chemotype, zearalenone, and NX-2 toxin profiles were determinedbased on chromatographic (LC-MS/MS) analysis.Differences in the genotype frequency were due to the target locus analyzed and year of isolation of the strain. The most common genotype and chemotype was 15-ADON in both seasons, but an increasing frequency of the 3-ADON chemotype was found in the non-epidemic season (2014/15). The strains were able to produce zearalenone and its masked derivatives, but not the type A trichothecene NX-2. This is the first report of the production of zearalenone and its modified mycotoxins by Fusarium graminearum species complex strains isolated from Argentina.