Biological Control of Tomato Damping-off and Potato Black Scurf by Seed Treatment with Trichoderma harzianum

Abstract

During the present study, the antagonistic potential of Trichoderma harzianum Rifai against Phytophthora infestans (Mont.) de Bary and Rhizoctonia solani Ktihn. was evaluated by dual culture technique. Its efficacy to inhibit pathogenic effects caused by these two pathogens was also evaluated on tomato and potato, under artificial inoculation conditions. On PDA medium, T. harzianum showed high level of antagonistic activity against all tested isolates of two pathogens. Appressorium -like structures were observed on R. solani hyphae. Treatment of tomato seeds with spore suspension of T. harzianum showed considerable decrease in pre-emergence damping-off disease incidence caused by P. infestans and R. solani, with biological control efficacy of 49.3% and 64.33% respectively. Seed treatment with T. harzianum also showed biological control efficacy of 66.03% for stem canker disease of tomato seedlings caused by R. solani. Trichoderma treatment significantly (≤ 0.05) reduced black scurf disease incidence caused by R. solani on potato during pot test experiments by 77.95% over untreated control. Although 0.2% carbendazim treatment highly protected tomato and potato plants, but it had a phytotoxic effect, however Trichoderma treatments had a positive effect on growth parameters studied as compared to the untreated control.