Isolation of mutants of Trichoderma harzianum with enhanced b-glucosidase production with ability to inhibit and the plant pathogen Sclerotinia sclerotiorum.

• Autor(a) principal: MELO, I. S. de
• Data de Publicação: 1996
• Outros Autores: FAULL, J. L., GRAEME-COOK, K.A., FRIGHETTO, R. T. S., SILVA, C. M. M. S.
• Tipo de documento: Capítulo de livro
• Idioma: eng
• Título da fonte: Repositório Institucional da EMBRAPA (Repository Open Access to Scientific Information from EMBRAPA - Alice)
• Texto Completo: http://www.alice.cnptia.embrapa.br/alice/handle/doc/12605
• topic: Isolation; Enhanced; B-glucosidase; Production; Pathogen; Sclerotinia Sclerotiorum; Trichoderma Harzianum; mutants

Antagonism of Trichoderma spp. against other microrganisms in general operates by exolysis, breaking down the walls of fungal pathogens. Trichoderma species seem to be the best source of extracellular cellulase that can solubilize highly ordered cellulose. Cell walls of sclerotia of slerotiorum usually contain chitin and b-glucans. Such sclerotia may be vulnerable to attack by many microrganisms. The objective of this research was the isolation of improved strains for b-glucosidase production. The new biotypes obtained from a wild strain of T. harzianum were isolated via UV light in solid medium containing wheat-bran. Two mutants produced significant amounts of extra cellular cellulase activity with b-glucosidase activity. The percentage of reduction of colony of S. sclerotiorum by antifungal activity was observed in vitro. The mutant 15+ presented 73% of inhibition of micelial growth. Hyphae morphology of the mutant strain, studied by SEM, shows that the hyphae tips are extremely branched. The wild-type did not produced any antibiotic activity.