The genetic diversity of Aspergillus flavus populations isolated from the peanut-cropped soils in the peanut-growing region at Cordoba
Province was evaluated by analysis of vegetative compatibility group (VCG). VCGs were determined through complementation assays
between nitrate-nonutilizing (NNO) mutants. Fifty-six VCGs were identified from 100 isolates. Twenty-five VCGs contained two or more
isolates and 31 VCGs contained only a single isolate. In general, there were significant differences among VCGs in aflatoxin and CPA
production. One VCG group included a single atoxigenic strain since it was neither aflatoxin nor cyclopiazonic acid producer. This isolate
could be useful as a biological control agent, since it was unable to form a stable heterokaryon in the complementation test with the other
isolates. Seven A. flavus isolated from soil were atypical because they simultaneously produced aflatoxins B, G and CPA.
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