In vitro Screening of Botanicals, Bio-Agents and Fungicides against Alternaria alternata (Fr.) Keissler, Causing Brinjal Blight Disease

Blight disease of brinjal caused by Alternariaalternatais one of the most destructive disease of brinjal which causes both qualitative and quantitative crop losses. In the present investigation, all plant extracts evaluated at 10% concentration exhibited antifungal activity against A. alternata. Soapnut rind extract was found the most effective which recorded leastcolony growth of 18.66 mm and the highest inhibition of 79.26%. Wild brinjal leaf extract was next best treatment with 31.33 mm growth and 65.18% inhibition. Among the eight bio-agents tested, Trichodermakoningii and T. longibrachiatumshowed complete inhibition of mycelial growthof A. alternata. T. harzianum showed significant effectiveness, with the lowest colony growth of 20.33 mm and 77.41% inhibition. Among the fungicides, Tebuconazole 25.9% EC, Hexaconazole 5% EC, Propiconazole 25% EC, Hexaconazole 4% + Zineb 68% (72% WP), Captan 70% + Hexaconazole 5% (75% WP) and Carboxin 37.5% + Thiram 37.5% (75% WS) each @ 0.1% concentration were found most significantly effective in inhibiting the mycelial growth of A. alternata with 100 per cent inhibition over control.