Growth of wild type and spreading colonial mutants of Neurospora crassa in batch culture and on agar medium.

Abstract

1. The colony radial growth rates (Kr) of wild type and spreading colonial mutants (spco) of Neurospora crassa were found to be a function of the strain's specific growth rate (α) and the width (w) of the colony's peripheral growth zone. $$K_\tau = \alpha w$$ 2. Except for one wild type strain and a temperature sensitive mutant (cot 3), all the 20 strains studied had approximately the same maximum specific growth rate. 3. The width of the peripheral growth zones of the strains varied from 493 to 6800 μm. 4. There was a direct relationship between the colony radial growth rates of the strains and the diameter and hyphal compartment (apical and intercalary) length of their leading hyphae. 5. The radial growth rate of spco 4 colonies increased linearly with medium depth.