Attempts to fix Trichoderma and Agaricus bisporous by conventional methods involving immersion in the fixatives of gluteraldehyde and osmium tetroxide failed to produce acceptable preservation for imaging in the SEM. A literature search produced a technique using vapor fixation. The following protocol produced fruiting bodies of Trichoderma with minimal shrinkage. Although it is a lengthy procedure, there is much less technician time than conventional procedures.
- Vaporfix mats of compost with the mycelia and fungal pathogen with 1% osmium tetroxide in 0.1M sodium cacodylate buffer placed into beem capsule lids placed near the mats in a disposalble petri dish for 4 days.
- Remove the lids and air dry the sample in the fume hood for 4 days.
- Mount onto an aluminum stub with a double sticky tab and colloidal silver
- Sputter-coat 10 nm of gold/palladium (2 min at 10 mAmps)
Quattlebaum, E.C. and G.R. Garner (1980) A Technique for preparing Beauveria spp. for scanning electron microscopy.Can. J. Bot. 58:1700-1703