Biocontrol efficacy of Trichoderma spp. against wilt of tomato caused by Fusarium oxysporum f. sp. lycopersici S. Sundaramoorthy and P. Balabaskar15_pdf.pdf036-040Tomato wilt, Fusarium oxysporum f. sp. lycopersici, Biological control, Trichoderma spp.877267The objective of this paper was to evaluate the efficacy of the native isolates of Trichoderma species to promote the growth and yield parameters of tomato and to manage Fusarium wilt disease under in vitro and in vivo conditions. The dominant pathogen, which causes Fusarium wilt of tomato, was isolated and identified as Fusarium oxysporum f. sp. lycopersici (FOL). Fifteen native Trichoderma antagonists were isolated from healthy tomato rhizosphere soil in different geographical regions. Under in vitro conditions, the results revealed that Trichoderma harzianum (ANR-1) isolate was found to effectively inhibit the radial mycelial growth of the pathogen (by 53%) when compared to all other isolates. Under greenhouse conditions, the application of Trichoderma harzianum (ANR-1) exhibited the least disease incidence (by 15.33%). Also tomato plants treated with Trichoderma harzianum (ANR-1) isolate showed a significant stimulatory effect on plant height (by 73.62 cm) and increased the dry weight (by 288.38 g) of tomato plants in comparison to other isolates and untreated control.