Effects of pH, NH4-N concentration, temperature, and storage period on basidiospore germination in an ectomycorrhizal ammonia fungus Hebeloma vinosophyllum

Basidiospore germination in an ectomycorrhizal ammonia fungus Hebeloma vinosophyllum was stimulated by 10–500 mM NH4Cl aqueous solution at pH 4.5–9.0, but not by pure water. The basidiospores germinated at 10°–35°C with an optimum at 25°–30°C. The highest germination percentage (83.0%) was observed in 100 mM NH4Cl aqueous solution adjusted to pH 8.0 by KOH, when the basidiospores were incubated at a density of 106 spores/ml at 30°C for 14 days. The percent germination value decreased with the increased duration of storage under both dry and wet conditions. Humidity and temperature affected the longevity of H. vinosophyllum basidiospores. The basidiospores maintained their germination ability longer under a dry condition than under a wet condition. The greatest longevity was accomplished by storage at 15°C under a dry condition.