Abstract
Two hundred and fifty seven temperature sensitive mutants of Neurospora crassa which were unable to grow at 35°C but grew at 25°C were isolated. 46 of these (irreparable temperature sensitive mutants) were unable to restore growth at 35°C by supplementing various nutrients. The irreparable temperature sensitive mutations were found which resulted in loss of viability of conidia, abnormality in morphology, loss of growing ability which is reversible by high osmotic pressure, loss of germinating ability of conidia or reduced ability to synthesize nucleic acids or protein at 35°C. Possible defects in macromolecule synthesis leading to loss of germinating ability of conidia were analysed in some of these mutants. Significance to study these temperature sensitive mutants was discussed.
