Effects of the herbicide dichlobenil on mitotic instability And haploidization of diploid strains of Aspergillus nidulans
The herbicide dichlobenil was compared with the standard haploidizing chemicals, benomyl and p-fluorophenylalanine, for its effects on mitotic stability and haploidizaftion of diploid colonies of A. nidulans. Three dufferebt duploid strains were used so that the influence of a gene conferring resistance to dichlobenil (dicA)on mitotic stability could also be determined. Diploid colonies gomozygous for the normal allele (dicAs // dicAs)and the mutant allele (dicAr // dicAr)or heterozygous at this locus (dicAr // dicAs)were transferred to dishes of CM supplemented with dichlobenil, benomyl or pfa and incubated at 37°C. The number of sectors scored after 4 and 8 days incubation was used as a measure for mitotic instability. This investigation has shown that dichlibenil causes an increase in the somatic instability of A. nidulans diploids, and is as effective as the haploidizing chemicals benomyl and p-fluoraphenylalanine (ofa)in generating haploid sectors.
