Physical and physiological quality of rice seeds in function of drying temperature and storage

Abstract

The objective with the work was to evaluate, during storage, the rice seeds physical and physiological quality, cultivar IRGA 424 RI, dried with different drying air temperatures. For such, rice seeds were harvested with a moisture content of 22%. Then, they were subjected to drying in a cross-flow dryer, operating in an intermittent system and using the 55 and 65 ºC drying air temperatures. After, samples containing 50 kg of seeds were stored in PP Woven Bags for 240 days. After drying and every 60 days, physical and physiological analyses were performed. The experiment was conducted under a completely randomized design, arranged in a split-plot scheme, with 4 replications. The physical quality, estimated by the seed hectoliter weight, decreased during storage, regardless of the drying air temperature. The germination percentage, as well as the vigor increased during storage, regardless of drying air temperature due to the dormancy overcoming process. The dry seeds with the highest drying air temperature showed less vigor throughout the storage, according to the cold test. The rice seeds drying with an air temperature of 65 ºC, promoted a higher drying speed and did not negatively influence the seeds physical and physiological quality, however, reduced the vigor.