Fusarium proliferatum, a fumonisin producing fungal species, is a causal ag
ent of a destructive disease of asparagus called Fusarium crown and root ro
t. The occurrence of fumonisin B-1 (FB1) and B-2 (FB2) in asparagus plants
heavily infected by F. proliferatum has been investigated together with the
capability of producing FB1 and FB2 by the fungus. Both fumonisins were de
tected in asparagus plants colonized by F, proliferatum at levels of 7.4 an
d 0.83 mu g/g (FB1) and 0.46 mu g/g and 0.06 mu g/g (FB2) in crown and stem
samples, respectively. Eight out of nine isolates of F. proliferatum teste
d for sexual compatibility proved to be members of Gibberella fujikuroi mat
ing population D. All nine isolates produced high amounts of FB1 and FB2 (u
p to 2504 and 946 mu g/g, respectively) when cultured on autoclaved maize k
ernels for 4 weeks at 25 degrees C. This is the first report of the natural
occurrence of fumonisins in asparagus plants.