DINOLFO Maria Ines
Species composition and genetic structure of Fusarium graminearum species complex populations affecting the main barley growing regions of South Africa
CASTAÑARES E.; DINOLFO M.I.; DEL PONTE E.; PAN D.; STENGLEIN S.A.
WILEY-BLACKWELL PUBLISHING, INC
Lugar: Londres; Año: 2016 vol. 65
Fusarium graminearum species complex (FGSC) is the main cause of Fusarium 21 Head Blight (FHB) of wheat and barley worldwide. In this study, 117 FGSC isolates obtained from barley grain produced in Argentina (n=43 isolates), Brazil (n=35), and Uruguay (n=39) were identified to species and trichothecene genotypes using a range of molecular assays, including grouping by amplified fragment length polymorphism (AFLP) and sequence related amplified polymorphism (SRAP) markers and sequencing of reductase (RED) and trichothecene 3-0-acetyltransferase (Tri101) for a smaller of collection of 24 isolates. The majority of the isolates (n=103) were identified as F. graminearum, which was the only species found in Argentina. In Uruguay, only one F. cortaderiae isolate was found among F. graminearum isolates. In Brazil, F. graminearum also dominated the collection (22/35) followed by F. meridionale (8/35), F. asiaticum (2/35), F. cortaderiae (2/35), and F. austroamericanum (1/35). The species were structured by trichothecene genotype: all F. graminearum were of the 15-acetyldeoxynivalenol (ADON), F. meridionale, F. asiaticum and F. cortaderiae were of the nivalenol (NIV), and F. austroamericanum was of the 3- ADON genotype. Both AFLP and SRAP data showed high levels of genetic variability, which was much higher within than among countries. The isolates were not structured by country of origin. SRAP analysis grouped F. graminearum in a separate cluster from the other species within the complex. AFLP analysis, however, failed to resolve the species into distinct clades with partial clustering of F. meridionale, F. austroamericanum, F. asiaticumand F. graminearum isolates.