Microcycle conidiation induced by partial nitrogen deprivation in Neurospora crassa

Premature macroconidiation occurs at the tips of germ tubes elongated as presumptive conidiophores from macroconidia of Neurospora crassa incubated at 37 °C in nitrogen-limited shaken cultures. The use of different nitrogen sources indicated that this differentiation process could be induced by ammonium deprivation. This microcycle conidiation was also promoted by carbon deprivation and found not to be strain specific. At 25 °C, microconidia were produced in nutrient-limited shaken cultures. The results present evidence that microcycle conidiation in N. crassa can be obtained by simple manipulation of the conditions of culture.