SYNCHRONOUS PRODUCTION OF CONIDIOPHORES AND CONIDIA OF NEUROSPORA CRASSA

Abstract

Neurospora mycelia were grown in Vogel's medium N. The mycelia were harvested and vacuum filtered to yield moist, mycelial mats 2 to 3 mm thick. The mycelial mats were placed in Petri dishes and incubated at 25°. On or about the third hour of incubation conidiophores appeared over the mycelial surface. The conidiophores differentiated into conidia on or about the eighth hour of incubation. The production of conidia continued for approximately 8 hours.The addition of 0.05 M malonate to the growth medium synchronized the appearance of the conidiophores on harvested moist mats of mycelia. The conidiophores so produced also approached synchrony in their differentiation into conidia. The uniformity of conidiophore production and the differentiation of conidiophores into large numbers of conidia were also influenced by both the length of aeration of the submerged mycelia and by treatment of the harvested mycelial mat with different buffers.There appeared to be a difference in the rate of germination for conidia harvested at different times from conidiophores of harvested mycelial mats. However, there was little difference in the germination rate for conidia produced from conidiophores of harvested mycelial mats and similar aged conidia grown on solidified medium N. The conidia, regardless of age or culture technique, retained a random capacity to germinate.