EFFECTS OF TEMPERATURE, INCUBATION ATMOSPHERE, AND MEDIUM COMPOSITION ON ARTHROSPORE FORMATION IN THE FUNGUS TRICHOPHYTON-MENTAGROPHYTES

Several growth conditions were found to allow abundant arthrospore formation in T. mentagrophytes. These included growth at 32-37°C on Sabouraud's medium (1% neopeptone, 4% glucose) and growth at temperature below 32°C solely on neopeptone or other complex peptide sources without the addition of glucose, a supplementary carbon source. Sabouraud's medium did not allow arthrospore formation at 30°C under normal atmospheric conditions. However, if oxygen tension were reduced by partial replacement of air with either N2 or CO2 arthrosporulation did occur on Sabouraud's medium at 30°C. The rate of germ tube elongation was lower under those conditions which supported arthrospore formation, suggesting a correlation between decreased rate of hyphal extension and arthrospore formation. Stimulation of arthrospore formation by sublethal concentrations of several antifungal agents tends to support this hypothesis.