DIFFERENTIAL SENSITIVITY OF DIPHENYL-SENSITIVE AND DIPHENYL-TOLERANT STRAINS OF FUNGI TO CHLORINATED NITROBENZENES AND TO SOME DIPHENYL DERIVATIVES

Abstract

In Hypomyces solani f. cucurbitae the inhibitory effect of diphenyl on spore germination, germ tube development, and subsequent growth was overcome by mutation to chloronitrobenzene tolerance at any of three previously known loci. Sectoring under the selective action of diphenyl similarly resulted in tolerance to chloronitrobenzenes. One mutant gene is sufficient to give the maximum diphenyl tolerance possible. Results of cross-tolerance tests with differentially sensitive strains of three other fungi showed the same relationship between diphenyl tolerance and chloronitrobenzene tolerance. Neither volatilities nor relative saturations were found to be of importance in an understanding of the reason for this relationship. Diphenyl-tolerant strains are also tolerant to compounds derived from diphenyl by simple substitutions. The magnitude of the tolerance may be influenced by the substituent, the position, and the fungus species.