RICE SEED TREATMENT AND RECOATING WITH POLYMERS : PHYSIOLOGICAL QUALITY AND RETENTION OF CHEMICAL PRODUCTS 1

The use of chemical seed treatment is an important tool in the protection of seedlings and has contributed to the increase of rice yield (Oryza sativa L.). The objective of this study was to evaluate the physiological quality and quantify the retention of chemical products in rice seeds treated with insecticide and fungicide coated with polymers. Six seed treatments were used: control, phytosanitary treatment and phytosanitary treatment and coating with the polymers, Florite 1127, GV5 Solid Resin, Polyseed CF and VermDynaseed. The physiological quality was evaluated by the test of germination and vigor by first count tests, germination speed index, shoot length, radicle length, seedling dry mass and sand emergence. To determine the retention of the active ingredients metalaxyl-M and thiamethoxam, an equipment called extractor was used. The experiment was organized in a completely randomized design (DIC) and the averages were separated by the Scott Knott test (p≤0.05). Seed treatment with the fungicide and insecticide, coated with the polymers, Florite 1127, Solid Resin GV5, Polyseed CF and VermDynaseed, did not affect the physiological quality of rice seeds. Solid Resin GV5, Polyseed CF and VermDynaseed polymers were efficient at retaining thiamethoxam in the rice seeds, preventing some of the active ingredients of the insecticide from being leached through the sand columns immediately after the simulated pluvial precipitation.