Efeitos dos tratamentos com fungicidas e inseticidas em diferentes épocas na qualidade de sementes de soja armazenadas

Abstract

This study was developed to determine which active ingredients have the ability to influence the germination and vigor of soybean seeds treated with insecticides and fungicides after certain storage periods. For this research, germination and vigor tests were performed using the accelerated aging method. The products Clothianidin, Pyraclostrobin + Thiophane Methyl + Fipronil and Fluxiodinil + Metalaxyl-M were used, whose effects were analyzed during the periods 0, 15, 30 and 45 days after the treatment of soybean seeds. For the germination tests, the treated seeds, in each storage period, were planted on germination paper previously moistened with 2.5 times the weight of the paper in water and distributed in 4 replicates of 50 seeds, subsequently placed in a continuous temperature germinator at a temperature of 25º C. After 5 days, the normal seedlings were counted. To evaluate the vigor, the accelerated aging test was used. 200 seeds were placed in a gerbox, which remained for 48 hours in an accelerated aging chamber at 41°C and 90% humidity. After this period, the seeds were placed to germinate on sheets of germination paper moistened with water 2.5 times the weight of the paper and planted in 4 replicates of 50 seeds and then placed in the continuous temperature germinator at a temperature of 25°C. After 5 days, the normal seedlings were counted. The germination test showed that the treatment with Pyraclostrobin + Thiophane Methyl + Fipronil had germination greater than 80%, but did not differ from the treatments containing Clothianidin and Fluxiodinil + Metalaxyl-M. However, all treatments had higher averages than the control in all storage periods. The seed vigor test treated with Pyraclostrobin + Thiophane Methyl + Fipronil and Fluxiodinil + Metalaxyl-M showed the highest germination averages, followed by Clothianidin, which was superior to the control. All treatments had averages above 70%, while the control was below this value. The treatments with Pyraclostrobin + Thiophane Methyl + Fipronil, Fluxiodinil + Metalaxyl-M and Clothianidin provided the best effect on soybean seed germination over 45 days of storage. The treatments Pyraclostrobin + Thiophane Methyl + Fipronil and Fluxiodinil + Metalaxyl-M provided the best effect on soybean seedling vigor. It was observed that products containing insecticides and fungicides in combination provide a higher germination rate and vigor for soybean seeds for a longer storage period.