Genetic characterisation of New Zealand and Australian wine yeasts. Occurrence of killer systems and homothallism.

Twenty five culture wine yeast strains from New Zealand and Australia were examined for killer capability or sensitivity. Eight yeast strains were K2 + killers, six of the K2 + R1 - R3 + phenotype and two of the K2 + R1 - R3 - phenotype. The seventeen sensitive strains were separated into four phenotype classes. The homothallic life cycle was detected in twenty-one strains and one further strain is probably triploid.