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The protoplast formation and intergeneric protoplast fusion between Gliocladium virens and Trichoderma harzianum were attempted to obtain fusants. Protoplast formation was the most effective when the strains were treated with concentration of 5 ㎎/㎖ of Novozyme 234 and Cellulase at 25℃ for 3 hours in phosphate buffer, pH 6.5, supplemented with 0.6 M sorbitol as osmotic stabilizer. Auxotrophic mutants of G. vireos G88 did not grow in minimal medium and benomyl resistant T. harzianum T95 from wild types, however, was selected by treatment with UV light as genetic marker to isolate fusants. When the intergeneric protoplast fusion between G. virens G88 and T. harzianum T95 was carried out using 30% PEG 4000 containing 10 mM CaCl₂, and 50 mM glycine (pH 8.5) as fusogenic agent at 25℃ for 10-15 min, the fusion frequency was 0.8×10^(-4). Fusants obtained from intergeneric protoplast fusion were spontaneously segregated into various strains by continous culture on complete medium. Several intergeneric hybrids were classified into three types: parent-like hybrids, segregants, and recombinants.
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