Genetic Variants Derived from Autopolyploid Strains ofTrichoderma reeseiQM 9414

Abstract

Autopolyploid strains were isolated from auxotrophic mutants, no. 77 (lys-), no. 77-25(lysmeC), and a cycloheximide 500 Ilg/ml resistant mutant, CR50 derived from T. reese; QM 9414 by 0.1% (w/v) colchicine treatment for 24hr and 72hr at 30°C. An autopolyploid strain, 77-25(24)-1, showed higher cellulase productivity especially in Avicel-hydrolyzing activity. When autopolyploid strains were treated with benomyl, trypan blue, and coumarin, various genetic variants in growth rate, conidial formation, and cellulase productivity could be isolated in addition to the 3 types of fruit-body-like stroctures. It was considered that autopolyploid formation by colchicine and benomyl treatment of autopolyploid strains were effective in breeding of T. reese; QM 9414.