In vitro Evaluation of Fungicides and Plant Derived Extracts on Mycelial Growth of Alternaria brassicae

Mustard (Brassica juncea) is one among the major oilseed crops in India grown during Rabi season. Alternaria blight of mustard caused by Alternaria brassicae is most widespread and destructive disease of mustard causing major yield losses that may range from 15 to 71 per cent in productivity and 14 to 36 per cent in oil. An experiment was conducted at the laboratory of the Department of Plant Pathology, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj, Uttar Pradesh, India. To test the efficacy of different treatments viz., Carbendazim @ 0.1%, Hexaconazole @ 0.05%, Carbendazim + Mancozeb @ 0.2%, Mancozeb @ 0.2%, Chilli (Capsicum annum) and Alstonia (Alstonia scholaris) @ 10% against Alternaria brassicae under in vitro condition. Fungicides and botanicals were tested through the poisoned food technique at 10 % concentrations and 168 hours of incubation. The Minimum radial growth was observed in Carbendazim + Mancozeb (0 mm) followed by Hexaconazole (5.28 mm), Mancozeb (6.25 mm), Carbendazim (14.25 mm), Chilli leaf extract (69.12 mm) and Alstonia leaf extract (84.23 mm) as compared to Control (90 mm) untreated check. Carbendazim + Mancozeb were found most effective in inhibition of mycelial growth in in vitro. This study aimed to control it using a range of cost-effective and commercially available chemical fungicides. Therefore, an attempt was made to assess the effectiveness of these fungicides against Alternaria blight in mustard in vitro.