Abstract
To establish low chemical input disease protection for rice plants, we designed a seed disinfection method using hot water to control seed-borne fungal and bacterial rice diseases. In this study, three sets of 10-kg weight seeds infested with Fusarium moniliforme, Pyricularia oryzae or Pseudomonas plantarii were immersed in 200l of hot water at 58 or 60°C for 10 to 20min using an experimental machine that could accurately maintain the water temperature (±0.1°C). The occurrence of each disease and the rate of seedling emergence in the nursery beds were observed after the hot water treatment. Hot water immersion was just as effective as conventional chemical seed disinfection in controlling the diseases. In a germination test, more than 90% seed germination was obtained with 20min at 58°C or 15min at 60°C for eight nonglutinous rice cultivars, but not for three glutinous rice cultivars. From these results, hot water immersion for seed disinfection is a promising method compared to conventional chemical seed disinfection methods.
