GENETIC-ANALYSIS OF RESISTANCE TO FENPROPIMORPH IN ASPERGILLUS-NIGER

Resistance to the morpholine-fungicide fenpropimorph was studied in As pergillus niger and A. nidulans. Mass selection of conidia of A. nidul ans on agar amended with the fungicide at different concentrations did not yield of resistant mutants, even after UV-treatment of the conidi a. In contrast, similar experiments with A. niger generated many fenpr opimorph-resistant mutants. The mutants displayed cross-resistance to fenpropidin and generally showed wild-type sensitivity to the unrelate d toxicants fenarimol and cycloheximide. Genetic analysis of fenpropim orph resistance in A. niger was carried out by means of the parasexual cycle. In the mutants tested, two genes located on linkage group II w ere involved in fenpropimorph resistance. Dominance tests showed that resistance to fenpropimorph in A. niger is recessive.