Evaluation of different fungicides in vitro against Phomopsis vexans causing stem blight and fruit rot in brinjal

Abstract

The Brinjal (Solanuum melongena L.) is principal vegetable crops grown in the tropical and subtropical areas. Stem blight and fruit rot caused by Phomopsis vexans (Sacc. and Syd.) Harter, is an important disease of brinjal inflicting heavy losses. It has been reported that P. vexans reduces yield up to 20% and marketable value of the crop nearly 20 to 30%. Therefore, in present studies 19 fungicides tested in vitro at three concentrations by poisoned food technique for evaluating their efficacy against P. vexans. Among systemic fungicides at 500 ppm significantly highest average mycelial growth inhibition was with carbendazim and propiconazole recorded i.e. 92.51% followed by hexaconazole (57.49%) and tebuconazole (56.57%), thiophanate methyl (52.08%) and azoxystrobin (45.83%). Among non-systemic fungicides at 2500 ppm significantly highest average mycelial growth inhibition was with mancozeb, propineb and chlorothalonil recorded i.e. 92.47% followed by zineb (69.58%), thiram (53.81%), copper oxychloride (49.13%) and Sulphur (40.88%). Among ready mix fungicides 2000 ppm significantly highest average mycelial growth inhibition was recorded in carboxin 37.5% + thiram 37.5%, carbendazim 12% + mancozeb 63% and pyraclostrobin 12.5% + epoxiconazole 4.7% i.e. 92.49% followed by pyraclostrobin 5% + mitiram 55% (72.96%), captan 70 % + hexaconazole 5 % (53.50%) and hexaconazole 4% + zineb 68% (38.80 %).