Sheath blight and drought stress management in rice (Oryza sativa) through Trichoderma spp.

Abstract

Sheath blight of rice caused by Rhizoctonia solani Kuhn is a major rice diseases worldwide, and cause up to 50% yield losses depending upon its severity. Native biocontrol agents were isolated from rice rhizospheric soil of different region and NADEP compost. Fourteen strains of Trichoderma were isolated and screened in vitro against Rhizoctonia solani causing sheath blight of rice through dual culture technique. Among all tested isolates under in vitro conditions Trichoderma BHU-11, T-4 and BHU-8 showed the maximum inhibition for Rhizoctonia solani (71.48%, 67.28% and 63.89%, respectively). These strains of Trichoderma were also taken for checking drought tolerance in rice crop. Trichoderma strains when applied as seed + root dip treatment showed reduction of disease incidence. It also acted as plant growth promoter and increased the number of tillers/hill, plant height and yield of the crop. Trichoderma alters the drought response including drought avoidance through different morpho-physiological and biochemical adaptations, and enhanced drought recovery. The root colonization by Trichoderma increased the growth of roots and plant productivity. Biochemical studies showed the ability of Trichoderma BHU-11, T-4 and BHU-8 to produce high level phenol and proline contents in Trichoderma treated stress challenged plants and higher accumulation of chlorophyll in Trichoderma treated plants.