USE OF DUAL-STAIN FLUORESCENCE MICROSCOPY TO OBSERVE ANTAGONISM OF PYRENOPHORA-TRITICI-REPENTIS BY LIMONOMYCES-ROSEIPELLIS IN WHEAT STRAW

A procedure was developed for differential fluorescence staining of the wheat tan spot pathogen, Pyrenophora tritici-repentis, and its antagonist, Limonomyces roseipellis. P. tritici-repentis was stained specifically by indirect immunofluorescence with the green fluorochrome FITC, and both fungi were stained red with a nonspecific lectin-conjugated fluorochrome (TRITC). Toluidine blue-O was used as a counterstain for observation of TRITC staining. In dual-stained sections of autoclaved wheat straw that was colonized by the two fungi, L. roseipellis was observed to grow in close association with and to penetrate hyphae of P. triticirepentis.