Antagonistic potential of Trichoderma hamatum against Alternaria porri causing purple blotch disease of onion through Gas chromatography-mass spectrometry (GCMS) analysis

Alternaria porri causing purple blotch disease of onion is a destructive phytopathogen which causes severe loss in productivity. The present study aimed to unravel the antagonistic potential and efficacy volatile organic compounds produced by various Trichoderma spp. against A. through Gas chromatography-mass spectrometry (GCMS) analysis. Ten isolates species were isolated from rhizospheric soil healthy plants. Upon paired plate technique, vitro ten tested virulent isolate infected TIM2 showed 76.29 per cent inhibition on mycelial growth pathogen. effective was identified as hamatum analysis rDNA internal transcribed spacers (ITS) region it subjected GC-MS result GCMS indicated highest peak area retention time with major antimicrobial bioactive like Tetradecane, 2,6,10-trimethy (20.327), (1.22) Dodecane, 2-cyclohexyl (20.079), (2.14), Heptadecane (21.222), (9.50), Octadecane (22.379), (3.58), Eicosane, 9-cyclohexyl (22.578), (1.84), 2-Propenoic acid, pentadecyl ester (23.400), (10.37), 2,6,10,14-tetramethyl (23.567), Eicosane (27.311), (2.34), Hexadecanoic methyl (27.918), (4.43), n-Hexadecanoic acid (29.156), (3.59) Tetrapentacontane, 1,54-dibromo (31.906), (3.33). These crude extracts exhibited stronger antifungal activity porri. Hence application T. for management highly supress pathogen reduce incidence.