Growth patterns of adenine-3B; supersuppressor strains of Neurospora crassa.

The interaction between several suppressible ad-3B alleles and several supersuppressor genes had been examined both quantitatively and qualitatively in a tetrad analysis. Quantitatively, there is a good deal of variation in mean growth rates of cultures showing supersuppression: part of this variation can be attributed to variation in the suppressibility of ad-3B alleles, part to variation of suppression efficiency of ssu alleles, and part to the action of modifying genes. Qualitatively, ad-3B; ssu cultures nearly always show cyclic stop-start growth patterns. Escape from stop-start growth to wild-type growth is common.