Laboratory Culture and Ascocarp Development of Podosordaria Leporina

SUMMARY

Successful culture of Podosordaria leporina in the laboratory requires a medium low in nitrogen. Stromatization and ascocarp formation occur when the mycelium receives daily exposure to light from the blue portion of the spectrum over a period of 10–12 days. Under these conditions a pinkish-orange pigment is produced in the mycelium. The formation of stremata with ascocarps is always accompanied by the production of pigment and requires illumination. Maximum growth and fructification occur at 25 C. Podosordaria leporina has a typically xylariaceous centrum consisting of paraphyses and cylindrical asci in perithecia embedded in the stromata. Each ascus has an apical amyloid plug and typically produces eight gibbous, dark, binucleate ascospores. As perithecia develop, the stromatal surface becomes covered with microconidia, which are capable of propagating the fungus. Single ascospore and single conidial cultures are capable of producing fertile stromata; the fungus is probably homothallic. Observations made on laboratory-grown cultures suggest that Podosordaria is not distinct from Poronia.