Production of endoglucanase by Trichoderma for control of phytopathogenic fungus Sclerotium rolfsii.

The three clones of Trichoderma were cloned in the yeast expression vector pYES2/CT namely, â-1, 6-endoglucanase from Trichoderma harzianum (pYESH2) and Trichoderma virens (pYESV1) and â-1, 4-endoglucanase from Trichoderma reesei (pYESR1). These were screened for glucanase activity in yeast host Saccharomyces cerevisiae strain INVSc1. Out of these organisms, a strain identified as T. reesei Rifai secreted highest activities. In vitro production of endoglucanase by T. reesei, a mycoparasite of phytopathogenic fungi, was examined under inducible conditions of GAL1 promoter of yeast vector pYES2/CT. Enzyme production was significantly influenced by the 2% galactose incorporated into the medium and was stimulated by acidic pH from 5.5 to 6.0. Galactose (2%) addition along with SC-U medium enhanced the production of these enzymes. Growth of S. rolfsii was significantly inhibited (based on the radial diameter of S. rolfsii) by enzyme preparations from Trichoderma. T. reesei has shown three times more, T. harzianum and T. virens has shown twice the activity when compared to control INVSc1 having pYES2/CT vector as a control.