The objective of this study was to evaluate the effect of chemical treatments during storage on the health and physiological quality of rice seeds with different moisture contents. Two rice seeds lots were used, cv EL PASO 144, with different moisture and health levels. To formulate the fungicide, 10 mL (1%), 20 mL (2%) and 30 mL (3%) of water were mixed with the fungicide Carboxin/Thiram (300 mL/ 100 Kg of seeds). The same water percentages, without addition of the fungicide, and also a control, constituted the seven treatments. The seeds were stored in hermetically-sealed recipients for eight months and were subsequently evaluated for moisture content, standard germination, vigor and health. Biochemical evaluation of the seeds was made by using electrophoresis of enzymatic systems to determine the activity of the enzymes: acid phosphatasis, alcohol dehydrogenasis, glutamate oxalacetate transaminase, esterase and α-amylase. The statistical design was of completely randomized blocks with three replications. The beneficial effect of the fungicide on physiological quality was evident immediately after the seed treatment. The results showed that the germination and vigor of treated seeds decreased after 60 days storage. The fungicide used in the seed treatment was efficient in reducing fungal incidence on the rice seeds. The high moisture associated with the fungicide applied accelerated the deterioration of seeds stored hermetically. It was not possible to identify the effect of the fungicide on the expression of enzymes in viable seeds.
Oryza sativa L.; sanitary; vigor; storage; Carboxin/Thiram
