The germination of basidiospores from commercial and wild-collected isolates of Agaricus bisporus (= A. brunnescens)

A standard set of conditions yielding highly reproducible germination kinetics for basidiospores of the commercial mushroom Agaricus bisporus is described. Spores of three commercial, one wild-collected, and one intraspecies hybrid were examined. The effects of presence or absence of growing mycelium, temperature, culture media, and spore age are described. Cycloheximide completely blocked basidiospore germination and the incorporation of [3H]leucine into protein, whereas actinomycin D had no effect on germ tube emergence. Furthermore, [3H]uridine is not incorporated into spores before or during germination, neither in the presence nor absence of actinomycin D. Two types of basidiospore dormancy exist for A. bisporus: (i) exogenously dormant spores and (ii) constitutively dormant spores, both of the group II type in which protein synthesis precedes RNA synthesis.Key words: spore, germination, Agaricus, basidiomycete.