title: A Novel Population of Fusarium fujikuroi Isolated from Southeastern U.S. Winegrapes Reveals the Need to Re-Evaluate the Species' Fumonisin Production.
abstract: Mycotoxins pose a challenge to a safe food supply worldwide, and their threat is expected to worsen with our changing climate. The need for diligence is exemplified by the discovery of fumonisin B2 in wine, which joins ochratoxin A as a mycotoxin of concern in the grape-wine chain. To elucidate the mycotoxin risk in southeastern American wine, grape samples were collected from vineyards during harvest in 2013 and potentially mycotoxigenic fungi (Fusarium and Aspergillus) were isolated from the samples. Numerous Fusarium isolates were recovered and identified to the species level by comparison of translation elongation factor 1-α gene sequences to verified strains. Fusarium fujikuroi was the most abundant species recovered (239 isolates), followed by F. proliferatum (52), F. incarnatum-equiseti (14), F. oxysporum (7), F. concentricum (1), and F. solani (1). In vitro assays quantified fumonisin production for representative isolates via liquid chromatography-tandem mass spectrometry. Surprisingly, nearly all F. fujikuroi isolates produced fumonisins B1, B2, and B3 at levels comparable to both the F. proliferatum isolates and the positive control, Fusarium verticillioides. Such capacity for fumonisin production refutes the generally accepted notion that F. fujikuroi produces undetectable or low levels of fumonisins and provides evidence to reconsider this species as a mycotoxigenic threat to economically significant crops.
authors: Department of Plant Pathology, The University of Georgia, Athens, GA 30602, USA. stephbolton@gmail.com.
authors: Stephanie L
authors: SL
authors: Bolton
authors: Department of Plant Pathology, The University of Georgia, Athens, GA 30602, USA. pbrannen@uga.edu.
authors: Phillip M
authors: PM
authors: Brannen
authors: U.S. National Poultry Research Center, R.B. Russell Research Center, USDA-ARS, Toxicology and Mycotoxin Research Unit, Athens, GA 30605, USA. anthony.glenn@ars.usda.gov.
authors: Anthony E
authors: AE
authors: Glenn
mesh_terms: D018556:Crops, Agricultural / Q000382:microbiology; D004271:DNA, Fungal / Q000235:genetics; D005506:Food Contamination / Q000032:analysis; D005516:Food Microbiology; D005638:Fruit / Q000382:microbiology; D037341:Fumonisins / Q000032:analysis*; D005670:Fusarium / Q000145:classification* / Q000254:growth & development / Q000302:isolation & purification; D058974:Phylogeography; D015144:Southeastern United States; D027843:Vitis / Q000382:microbiology*
chemical_list: D004271:DNA, Fungal; D037341:Fumonisins; C056934:fumonisin B2; C056933:fumonisin B1
keywords: Fusarium; Fusarium fujikuroi; Fusarium proliferatum; Vitis vinifera; fumonisin; grapes; ochratoxin A