Effects of Rate and Timing of Fungicide Applications on Incidence and Severity of Sheath Blight and Grain Yield of Rice

Incidence and severity of rice sheath blight, caused by Rhizoctonia sofani, were monitored in 1989 and 1990 from the green ring growth stage to maturity in nonsprayed, inoculated plots and inoculated plots sprayed with propiconazole and other fungicides at different rates and growth stages. Single green ring applications of propiconazole at 0.18, 0.32, or 0.48 kg a.i./ha and sequential green ring and boot sprays (0.18+0.18 and 0.32+0.32 kg a.i./ha) effectively reduced disease incidence over time