Sporidesmin production by Pithomyces chartarum isolates from Australia, Brazil, New Zealand and Uruguay

Isolates of Pithomyces chartarum obtained from pasture samples originating from Australia, Brazil, New Zealand and Uruguay were evaluated for their ability to produce sporidesmin. Only isolates that produced enough spores to confirm the presence or absence of sporidesmin were evaluated. Samples from the countries examined gave proportions of sporidesmin-producing isolates of: Australia, 67% of 207 isolates; Brazil, 2% of 51 isolates; New Zealand, 86% of 391 isolates and Uruguay, 28% of 182 isolates. Considerable variations in the ability to produce sporidesmin were found, not only between countries but between samples taken from the same country.