ISOLATION, CHARACTERIZATION AND GENETIC-ANALYSIS OF MUTANTS OF ASPERGILLUS-NIDULANS RESISTANT TO THE HERBICIDE DICHLOBENIL

Thirty one spontaneous mutants of Aspergillus nidulans were recovered from 5·2 × 106 conidia incubated on synthetic medium supplemented with 100–200 μg dichlobenil ml−1. The mutants varied considerably in morphology, growth rate, conidiation, osmotic sensitivity and degree of resistance to the herbicide. All mutants were cross-resistant to the aromatic hydrocarbon fungicides quintozene and tolclofos methyl, and the dicarboximide fungicide vinclozolin. Both the herbicide and the fungicides enhanced growth and conidiation of some mutants. Genetic analysis of seven mutants with diverse phenotypes showed that they each carried a single gene for dichlobenil resistance that was tightly linked to methH on linkage group III. The mutant alleles were dominant to the wild-type gene. © 1990, British Mycological Society. All rights reserved.