In vitro evaluation of fungicides against Pyricularia oryzae (Cav.) causing rice blast disease

The present In-vitro study was conducted at pathology laboratory, University of agricultural sciences, GKVK, Bangalore, Karnataka, India during February 2016 to evaluate fungicides against rice blast disease caused by Pyricularia oryzae (Cav.). The six different fungicides viz., Tebuconazole + Trifloxystrobin (50% + 25%) WG, Tebuconazole (25.9% EC), Azoxystrobin (23% EC), Captan (50% WP), Carbendazim (50% WP), and Tricyclazole (75% WP) were tested at three different concentrations of 50, 100 and 150ppm by using the poisoned food technique. Among the six different fungicides, highest per cent inhibition of mycelial growth of fungus was recorded in Tebuconazole + Trifloxystrobin (50% + 25%) WG (98.40, 99.90 and 99.90%) at all the concentration tested with mean of 99.40 per cent followed by Tebuconazole (25.9% EC) with the inhibition of 97.73, 99.90 and 99.90 per cent respectively with mean of 99.18 per cent. Minimum inhibition was observed in Tricyclazole (75% WP), with 55.83, 63.62 and 70.52 per cent inhibition at 50, 100 and 150ppm concentration respectively with a mean of 63.66 per cent. In general, the inhibition of radial growth of fungus increased with increase in concentration of each fungicide.