New combination fungicide mancozeb 68% + hexaconazole 4% WG against blast and sheath blight disease in rice

Abstract

Among the fungal diseases of rice, blast and sheath blight are menace to the rice cultivation in major parts of India and are primarily managed through fungicides. The present study was conducted to evaluate the bio-efficacy and phytotoxicity of new fungicide combination mancozeb 68% + hexaconazole 4% WG against blast and sheath blight at three different concentrations (1000 g/ha; 1250 g/ha and 1500 g/ha). The fungicide molecule was not very effective against rice blast disease even at higher concentrations. However, it was highly effective against sheath blight of rice at all the three concentrations tested and significantly reduced the disease severity compared to unsprayed control and further increased the grain yield in BPT 5204 (5552 kg/ha at 1500 g/ha) compared to unsprayed control (4172 kg/ha) during 2014. The molecule did not exhibit any phytotoxicity symptoms on rice plants even at higher concentrations (1250 g/ha, 2500 g/ha and 3000 g/ha).