- The objectives of this study were to determine drying curve and drying rate of the white-oat seeds and the effect of this intermittent drying on the physiological and industrial quality, having as goal to improve the drying technology to oat seed producters. The experiment was carried out in the seed processing unit of Instituto Agronômico do Paraná (IAPAR), in Ponta Grossa - PR, Brazil. The seeds of the cultivar UFRGS 14 were dried from 24.8% of initial water content to 13.6% in a dryer ?KW2? with a intermittent method. Four treatments were used: drying
until 13.6% water content, in oven without forced ventilation regulated at 38oC; intermittent drying for 90 minutes, the growing temperature of 15oC to every 30 minutes, starting from 35oC, followed by drying in oven at 38oC; intermittent drying for 150 minutes, being 90 minutes the growing temperature of 15oC to every 30 minutes and 60 minutes the constant temperature of 80oC, followed by the drying in oven at 38oC; intermittent drying for 240 minutes, being 90 minutes the growing temperature of 15oC every 30 minutes, 60 minutes the constant temperature of 80oC and 90 minutes the decreasing temperature in 10oC to every 30 minutes. The air was heated up to 80oC in the superior drying chamber. Periodic seed samples were colected during the drying. Germination, seedling vigor classification, accelerated aging, speed and field emergency tests were used to evaluate the physiological quality immediately after drying and after six months of storage. The industrial quality was determined by industrial performance, and unshelled and broken grains percentage. The seed water content and mass temperature were determined during the drying. The water content and the seed mass temperature data were analyzed by polynomial regression, and the physiological and industrial quality, data were submitted to multiple average comparison procedure. The conclusions were: high air drying temperatures (80oC) don?t affect in both immediate or latent way, the physiological and industrial white-oat seeds qualities; in the intermittent drying the drying rate reaches 2.8 percentile water points per hour and the white-oat seeds drying curve is represented by an equation of first degree.