The expression of extracellular fungal cell wall hydrolytic enzymes in different Trichoderma harzianum isolates correlates with their ability to control Pyrenochaeta lycopersici

• Main Authors: LUZ MARÍA PÉREZ, XIMENA BESOAÍN, MAURICIO REYES, GONZALO PARDO, JAIME MONTEALEGRE
• Format: Article
• Language: English
• Published: BMC 2002-01-01
• Series: Biological Research
• Subjects: Trichoderma harzianum; Pyrenochaeta lycopersici; biological control; corky root; tomato root diseases
• Online Access: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602002000300014

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 ß -1,3-endoglucanases and/or proteases appeared to have less significance than endochitinases in the biological control of P. lycopersici