<i>TRICHODERMA HARZIANUM AS BIOFUNGICIDE IN THE CONTROL OF PHYTOPHTHORA CAPSICI IN PEPPER (CAPSICUM ANNUUM L.) PLANTS</i>

Abstract

During experiments in pepper plants using Trichoderma harzianum (T.h.) to control Phytophthora capsici (P.c.), the causal agent of root rot in pepper, we have optimised biomass production of the antagonist by comparing its growth in three different culture media and supports. Compared with Czapek liquid and PDB, the most advantageous medium was Water-Oats-Vermiculite, since this provided the most rapid and abundant growth, showed the highest degree of viability and it was cheap for use as a soil inoculum. In vitro antagonism tests involving against in PDA medium enriched with Laminarine: L-glucose (3:1, v/v) showed that T.h. increases hydrolytic nzymes levels (enzymatic lyses), exercises a greater competition for space and nutrients, and directly interacts with the pathogen (micro-parasitism), all of which play an important part in reducing and destroying the pathogenic colonies. The filtrate of the PDB medium in which T.h. had been cultured affected the root growth of seedlings in vitro. In vivo experiments the plants grown from treated seeds showed a greater dry weight than the control plants. Treatment with reduced the wilt caused by P.c. in pepper plants by up to 65%.