Collection and concentration of spores of Pithomyces chartarum from herbage and harvesting from ryecorn cultures

Abstract

A description is given of the techniques for the collection and concentration of spores (conidia) of P. chartarum from grassland herbage, for chemical and biological assays for the toxin sporidesmin, which is implicated in facial eczema of sheep and cattle. A metal gauze and cotton wool filter system or a cyclone, both powered by an electric suction cleaner, are used for the collection of spores mixed with fine debris from herbage. The spores of P. chartarum are concentrated by rolling spores and debris on typing parchment to which the spores adhere, or by suction through fine nylon fabric with small glass cyclones; dry harvesting of spores grown on ryecorn is done with a cyclone. A wet spore harvesting technique is described. The field-cyclone technique may be used for “wet collection” from herbage for assessment of spore load when spore traps cannot operate and for collection of small insects and other fungi.