A New Pattern of Reproduction in Pyronema Domesticum

SUMMARY

The majority of the ascogonia which produced ascogenous hyphae did so after the trichogyne failed to complete plasmogamy in cultures of two isolates of Pyronema domesticum, a discomycete. Most of the ascogonia reproducing in this manner bore a trichogyne which failed to unite with a fertilizing element. Some of the trichogyne tips fused and established cytoplasmic continuity with an antheridium, sterile hypha, or the ascogonium which produced it, but cytoplasmic continuity was not established between the trichogyne base and ascogonium. Ascogenous hyphae were subsequently produced by these unfertilized ascogonia. Infrequently, plasmogamy involving an antheridium, sterile hypha, or ascogonium was completed. Further development of the apothecium followed the pattern established for an isolate of P. domesticum in which plasmogamy regularly occurred.