Antagonistic activity of native Trichoderma spp. and fluorescent Pseudomonads againstRhizoctonia solani causing sheath blight in rice crop

Abstract

Rice (Oryza sativa L.) is a cereal grain, it is the most widely consumed staple food for a large part of the world’shuman population, especially in Asia and Africa. Rice production is often subjected to several biotic and abiotic stresses ricesheath blight is one of the most destructive diseases causing great damage to rice yield and quality worldwide.Twentyrhizospheric soil samples of rice obtained during survey from different regions of Northern Karnataka were used for theisolation of Trichoderma spp. and fluorescent Pseudomonads. The antagonistic potential was studied by using dual culturetechnique. Among twenty Trichoderma spp., the highest inhibition (> 50%) was recorded in nine isolates which rangedfrom 54.20 to 65.10 per cent. The results obtained were highly significant between the different isolates and also over control.Among the twenty fluorescent Pseudomonads, the per cent inhibition was higher (> 50%) in twelve isolates which varied from51.92 to 81.79 per cent. The results obtained were highly significant between the different isolates and also over control.