Antifungal potential of native Trichoderma isolates against Pythium aphanidermatum causing Chilli damping-off

Efficacy of 23 Trichoderma isolates was tested for their ability to reduce the growth of Pythium aphanidermatum causing damping-off of chilli. Studies revealed that locally isolated Trichoderma harzianum showed the highest inhibition (98.1%) followed by T. asperellum (88.8%), T. hamatum (86.6%), T. longibrachiatum (85.2%) and T. koningiopsis (84.3%) and other Trichoderma spp. against the growth of P. aphanidermatum. Highly potential five isolates of Trichoderma were selected for pot culture evaluation for germination %, pre and post-emergence damping-off and growth parameter of chilli seedlings. Among five Trichoderma isolates, seed treatment with T. harzianum at 2×108 CFU ml-1 recorded highest germination (93.7%), shoot length (10.03 cm) and root length (05.65 cm) and was also better in reducing the pre and post emergence damping-off (84.3% and 85.0%, respectively) followed by T. asperellum and rest of the treatments. The antimicrobial volatile compounds isolated from T. harzianum were 6 pentyl-a-Pyrone, Heneicosane, Harzianic acid and 1, 2 Benzene dicarboxylic acid.