|Wilson, Jeffrey - Jeff|
Submitted to: Mycopathologia
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/5/2004
Publication Date: 5/1/2005
Citation: Jurjevic, Z., D.M. Wilson, J.P. Wilson, D.M. Geiser, J.H. Juba, W. Mubatanhema, G.C. Rains, and N. Widstrom. Fusarium species liseola section on pearl millet and corn and its relation with fumonisin production. 2005. Mycopathologia 159 (3):401-406.
Interpretive Summary: Society benefits when alternative crops are found to have useful characteristics not found in traditional crops. Pearl millet is a drought-tolerant forage grass which also produces a high-quality grain. The grain must have superior traits if it is to be economically important. Corn grown in the southern United States is frequently contaminated with mycotoxins, including fumonisins. Fumonisins can cause severe health effects in horses and swine, detrimental effects in ruminants and poultry, and have been associated with esophageal cancer in people. Corn and pearl millet produced in Georgia were evaluated for fumonisins in this study. We found that up to 91% of the corn samples in a given year were contaminated with fumonisins, but no fumonisins were detected in pearl millet. Fusarium verticillioides, the fungus that produces fumonisins in corn, was not present in the pearl millet samples. Instead, a closely related fungus, Fusarium pseudonygamai, was found in pearl millet. This is the first time this fungus has been found in the United States. Development of pearl millet as a drought-tolerant grain crop will provide an alternative feed grain with low mycotoxins to farmers and livestock producers in the southern United States.
Technical Abstract: This study was designed to identify Fusarium species of the Liseola section on pearl millet and corn crops grown in southeast Georgia, and to determine their influence on fumonisin production. Pearl millet and corn samples were collected in Georgia from 1996 to 1998. One hundred nineteen isolates of Fusaria from the Gibberella fujikuroi species complex from pearl millet were paired with mating population A (Fusarium verticillioides), D (Fusarium proliferatum) and F (Fusarium thapsinum) tester strains. Successful crosses were obtained with 50.4%, 10.1%, and 0.0% of these isolates with the A, D, and F tester strains, while 39.5% of the isolates did not form perithecia with any tester strains. Two typical, infertile isolates were characterized by DNA sequence comparisons and were identified as Fusarium pseudonygamai, which is the first known isolation of this species in the United States. Based on the pattern of cross-compatibility, conidiogenesis, and colony pigmentation, many of the infertile isolates probably belong to this species. Fumonisins FB1 and FB2 were not detected in any of the 81 analyzed pearl millet samples, consistent with the assumption that F. pseudonygamai does not produce fumonisins. Fusaria of the Liseola section were isolated from the 1996 to 1998 Georgia corn survey (162, 104 and 111 isolates respectively) and tested for mating compatibility. The incidence of isolates belonging to mating population A (F. verticillioides) ranged from 70.2% to 89.5%. In the 1996 to 1998 corn samples, 63% to 91% were contaminated with fumonisins, at levels ranging from 0.6 'g/g to 33.3 'g/g.