title: The expression of extracellular fungal cell wall hydrolytic enzymes in different Trichoderma harzianum isolates correlates with their ability to control Pyrenochaeta lycopersici.
abstract: Four isolates of Trichoderma harzianum (ThN3, Th11, Th12 and Th16) were selected for their ability to control the in vitro development of the tomato root pathogen Pyrenochaeta lycopersici. Analysis of the mechanisms involved in biocontrol showed that the formation of non-volatile metabolites appears to be one of those involved in biocontrol of P. lycopersici by all T. harzianum isolates tested. Nevertheless, the higher secretion of chitinases, both in number of isoenzymes and activity by the Th11 strain, correlated well with its higher ability to control this agent in laboratory and greenhouse experiments as compared to the other T. harzianum isolates tested. The secretion of beta-1,3-endoglucanases and/or proteases appeared to have less significance than endochitinases in the biological control of P. lycopersici.
authors.affiliation: Laboratorio de Bioquímica, Facultad Ciencias de la Salud, Universidad Andrés Bello, Sazie 2325, Santiago de Chile. lperez@abello.unab.cl
authors.forename: Luz María
authors.initials: LM
authors.lastname: Pérez
authors.forename: Ximena
authors.initials: X
authors.lastname: Besoaín
authors.forename: Mauricio
authors.initials: M
authors.lastname: Reyes
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Pardo
authors.forename: Jaime
authors.initials: J
authors.lastname: Montealegre
mesh_terms: D002473:Cell Wall / Q000378:metabolism*; D002688:Chitinases / Q000378:metabolism*; D010450:Endopeptidases / Q000378:metabolism*; D005110:Extracellular Space / Q000201:enzymology; D015971:Gene Expression Regulation, Enzymologic; D018551:Solanum lycopersicum / Q000201:enzymology / Q000382:microbiology*; D010572:Pest Control, Biological; D010935:Plant Diseases / Q000382:microbiology*; D014242:Trichoderma / Q000201:enzymology*
chemical_list: D002688:Chitinases; D010450:Endopeptidases