Species-specific primers resolve members of Fusarium section Fusarium. Taxonomic status of the edible "Quorn" fungus reevaluated.

Sixty-seven authentic isolates, representing six species from Fusarium section Fusarium (= section Discolor) were subjected to random amplified polymorphic DNA (RAPD) analysis and polymerase chain reaction using species-specific primers. Remarkably uniform RAPD banding patterns were obtained intraspecifically, irrespective of the geographical origin of the isolates or the host/substratum from which they were isolated. Isolates were also assessed for colony characteristics when grown on a defined minimal medium. The Quorn strain (ATCC 20334; previously considered to be F. graminearum) matched the F. venenatum strains exclusively in RAPD profile. In addition, equivalently sized DNA fragments amplified from ATCC 20334 and two authentic F. venenatum strains were identical with respect to DNA sequence. Our molecular and morphological data support the identification of the Quorn strain as F. venenatum Nirenberg (= F. sambucinum Fuckel sensu lato).