Testing the efficacy of different fungicides against Colletotrichum capsici under in vitro Conditions

Abstract:

The key crop for the global economy, the chilli (Capsicum annuum L.), is badly affected by fruit rot, which can reduce yields by up to 50%. The most popular method for controlling anthracnose is the use of chemical fungicides. Based on pathogenicity studies, isolate Cc-3 was recorded as the highest virulent with early and late symptoms on chilli fruit among 19 different isolates. Isolate Cc -3 was used for the study of the management of Colletotrichum capsici by evaluating different fungicides using poisoned food technique. The efficacy of different fungicides viz., carbendazim 50 % WP, captan 50% WP, copper oxy chloride 50 % WP, difeniconazole 25 % EC, tebuconazole 25.9 % EC, azoxystrobin 23 % SC, azoxystrobin 11 % + tebuconazole 18.3 % w/w SC, carbendazim 12 % + mancozeb 63 % WP, carbendazim 12 % + flusilazole 12.5 % SE, prochloraz 24.4 % + tebuconazole 12.15 % w/w EW, tebuconazole 50 % + trifoxystrobin 25 % WG, metiram 55 % + pyraclostrobin 5 % WG, picoxystrobin + tricyclazole 20.33 % w/w SC, hexaconazole 5 % + captan 70 % WP were tested against Colletotrichum capsici pathogen collected from pinapaka village of Khammam area under in vitro conditions. The results from in vitro studies on the different fungicides tested, the EC50/ ED50 (µg ml^-1) values shown less in Tebuconazole 25.9 % EC (18) followed by difenoconazole 25 % EC (115), carbendazim 12 % + mancozeb 63 % WP (316), hexaconazole 5 % + captan 70 % WP (406), carbendazim 25 % + flusilazole 12.5 % SE (549), azoxystrobin 11 % + tebuconazole 18.3 % w/w SC (689) and prochloraz 24.4 % + tebuconazole 12.1 % w/w EW (762). Minimum Inhibitory Concentration (MIC) was recorded lowest in tebuconazole 25.9 % EC (100 µg ml^-1) followed by difenoconazole 25 % EC (250 µg ml^-1) and highest was recorded in azoxystrobin 23 % SC (3500 µg ml^-1) among all the six individual fungicides. Minimum Inhibitory Concentration (MIC) was recorded lowest in carbendazim 12 % + mancozeb 63 % WP (1000 µg ml^-1) followed by hexaconazole 5 % + captan 70 % WP (1250 µg ml^-1) and highest was recorded in tebuconazole 50 % + trifloxystobin 25 % WG (4000 µg ml^-1) among all eight combination fungicides.