Efficacy of fungicides against Colletotrichum gloeosporioides causing mango anthracnose.
Suvarna J., Basha S. T., Hemalatha T. M., Reddy N. P. E.
Author Affiliation: Department of Plant Pathology, S V Agricultural College, Tirupati - 517 502, Andhra Pradesh, India.
Indian Journal of Plant Protection 37 : 201-203
Abstract : A total of 20 C. gloeosporioides isolates were collected from mango leaves showing anthracnose symptoms in Chittoor and Kadapa districts of Rayalaseema regions of Andhra Pradesh (India) and designated as Cg1 to Cg20. The efficacy of commonly used systemic, i.e. carbendazim 50% WP (50 & 100 ppm), thiophanate-methyl 70% WP (50 and 100), propioconazole 50% EC (25 and 50 ppm), and non-systemic fungicides, i.e. hexaconazole 25% EC (25 and 50 ppm), mancozeb 75% WP (500 and 1000 ppm) and copper oxychloride 50% WP (500 and 1000 ppm), was investigated in vitro against C. gloeosporioides [Glomerella cingulata] isolates by poisoned food technique. All the fungicides inhibited the growth of the pathogen. A significant reduction in radial growth of the isolates at the 2 concentrations of the tested fungicides was observed compared to the control. These results showed variation in the degree of sensitivity to the different fungicides among the isolates. All the isolates were classified under highly sensitive to sensitive categories both at 50 and 100 ppm concentrations for carbendazim. The same results were observed with thiophanate-methyl at 50 and 100 ppm and propioconazole at 25 and 50 ppm concentrations. Isolates Cg2, Cg6, Cg10, Cg13, Cg19, and Cg20 exhibited moderate resistance to hexaconazole at 25 and 50 ppm concentrations. Cg9 was resistant to mancozeb and Cg12 was resistant to copper oxychloride at 500 ppm and moderately resistant at 1000 ppm. The non-systemic fungicides mancozeb and copper oxychloride were less effective than the systemic fungicides.