Vol. 12, Issue 5 (2023)

Author(s):
Adyasha Das and Shyama Sundar Mahapatra

Abstract:
Use of biocontrol agents against soil borne pathogen is gaining importance in the present situation for eco-friendly management of soil borne diseases. Bioefficacy of native Trichoderma spp. has greater impact against soil borne pathogens of green gram. Native Trichoderma isolates were collected from soil rhizospheres of green gram from different agroclimatic zones of Odisha. Fusarium oxysporum and Sclerotium rolfsii were isolated from wilted green gram plants from different green gram plots. Isolate 5 inhibited 71.11% of radial growth of Fusarium oxysporum followed by Isolate 7 (60.11%) where as Isolate 5 reduced 60.18% of radial growth of Sclerotium rolfsii followed by Isolate 7 (54.31%). All the Trichoderma isolates produced toxic volatile metabolites having significant effect in reducing the radial growth of the test pathogens Fusarium oxysporum and Sclerotium rolfsii. Trichoderma isolate-5 inhibited the mycelial growth of test pathogen by 39.62% followed by isolate -7 with 38.60% of inhibition over control. In case of Sclerotium rolfsii also Trichoderma isolate -5 was found to be most efficient in reducing the mycelial growth of the test pathogen by 44.25%. The significantly maximum zone of inhibition for non-volatile metabolites of Trichoderma isolate -5 was found compared to other isolates with 39.64% inhibition against Fusarium oxysporum and 36.26% in case of Sclerotium rolfsii.