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Isolation of putative recombination mutants of Aspergillus nidulans

Tânia M.A. Domingues Zucchi

Departamento de Ciências Morfológicas, Laboratório de Genética, Faculdade de Odontologia de Ribeirão Preto, USP, 14049 Ribeirão Preto, SP, Brasil

ABSTRACT

A method was devised for the detection of mutants which produce altered frequencies of recombinants. Inspection of ascospore colonies, on a selective medium, can detect mutations (in one parent) that appear to affect recombination in the meth A - w A interval of linkage group II of Aspergillus nidulans, an interval which yields 1% recombinants.
Isolates resulting from N-methyl-N'-nitrosoguanidine treatment were crossed individually to a meth A17 strain. Using meth and w as markers, recombinants were detected by plating on selective medium, and classification for conidial color. The method has revealed several classes of mutants, including those showing meiotic recombination frequencies different from normal

Keywords: Recombination mutants; Aspergillus nidulans.

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