Efficacy of fungicides, biocontrol agents and botanicals against ring spot disease (Leptosphaeria sacchari Van de Brenda) of sugarcane.

Abstract

Sugarcane (Saccharum officinarum L) is an important cash and industrial crop of India. Ring spot (Leptosphaeria sacchari Van de Brenda) of sugarcane is one of miner disease which sporadically has become frequent occurring disease in some parts of Northern Karnataka. Pathogenicity of ring spot disease was proved by mycelial bit inoculation method. Further identified by produced mycelium septate, hyaline, sexually ascospores were ellipsoid, ends broadly obtuse, hyaline, three celled with second cell slightly swollen with a measured of 16.13 to 27.09 µm in length and 3.99-8.00 µm in breadth and asexually conidia were hyaline, pale brown in mass, ellipsoid to subfusoid, guttulate, one- celled with a measured of 5.67 to 9.66 µm in length and 3.99-5.88 µm in breadth. In vitro evaluation fungicides, plant extract and bioagents revealed that hexaconazole 5% EC (0.1%) , propiconazole 25% EC (0.15%) ,carbendazim 50% WP (0.15%) and thiophanate methyl 75% WP(0.15%) in systemic fungicides, Copper oxychloride 50% WP (0.2%), mancozeb (0.3%) in non-systemic fungicides, trycyclozole 18% + mancozeb 62% WP (0.05%), cabendazim 12% + mancozeb 63%, hexaconazole 18% + zineb 68% and captan 70% + hexaconazole 5% in combi products were most effective and leaf extract of Eucalyptus sp and Azadirachta indica @ 10 per cent concentration and Trichoderma viride and T. harzianum were most effective against L. sacchari.