Chitinase and laminarinase production in liquid culture by Trichoderma spp. and their role in biocontrol of wood decay fungi

This paper describes macro- and microassay methods to assess the production of the lytic enzymes laminarinase and chitinase, by a range of Trichoderma isolates, and investigates the effect of nutrient composition, glucose amendment and the addition of basidiomycete cell wall material on the production of these lytic enzymes. Large interstrain and interspecies differences exist in the levels of production of both enzymes. Total activities of the enzymes are greater when isolates are cultured in malt medium, but specific chitinase and laminarinase activities are higher in low nutrient conditions. Glucose repressed the production of both laminarinase and chitinase, although this effect was not common to all Trichoderma isolates for the latter enzyme. Cell walls of both N. lepideus and T. versicolor induced increased chitinase activity but this effect was Trichoderma species specific. Mycoparasitism involving lytic enzymes has been described as the mechanism of action of Trichoderma species in the biological control of commercially important plant pathogens. However, little information is available on the significance of this mechanism for the biological control of wood decay fungi. The importance of mycoparasitism as a mechanism in the biological control of wood decay fungi is briefly discussed.