AJUSTES METODOLÓGICOS DO TESTE DE HIPOCLORITO DE SÓDIO EM SEMENTES DE SOJ

Abstract

Mechanical damage is a major obstacle to the production of high-quality soybean seeds. The most critical stage in the entire production process is harvesting and processing, where there is the greatest risk of such damage occurring. The objective of this work was to develop a quick and practical methodology for evaluating mechanical damage in soybean seeds. The work was carried out in a factorial design with two 5x6 factors using different concentrations of sodium hypochlorite (4.75, 5.0, 5.25, 5.50 and 5.75%) and soaking times (3, 4, 5, 6, 7 and 10 min). The solutions were prepared from commercial 9% sodium hypochlorite, performing the necessary dilutions using the dilution equation C1V1 = C2V2. This treatment was applied to three soybean cultivars: Olimpo 80I82RSF IPRO, M7601 I2X, and Bônus 8579RSF IPRO, one batch of each, from 2023/2024 growing season, with four replicates of 100 seeds per treatment. For mechanical damage tests, a seed counter and the necessary sodium hypochlorite were used to prepare 1.0 liters of stock solution. The results indicated that, for soybean cultivars Bônus 8579 RSF IPRO and M7601 I2X, among the concentrations evaluated in this study, the 5.75% sodium hypochlorite solution associated with a treatment time of 3 minutes presented the lowest values of mechanical damage. For Olimpo 80I82 RSF IPRO cultivar, it was observed that a 5.75% sodium hypochlorite concentration combined with a 10-minute exposure time resulted in a lower rate of mechanical damage. However, the literature and technical recommendations from Embrapa indicate the use of a 5.25% solution, emphasizing that further research comparing different concentrations in different batches is necessary to validate possible methodological adjustments, since these conditions do not compromise the reliability of the results and allow for greater speed in the evaluation process. KEYWORDS: Stamina test; Soaking; Mechanical damage; Glycine max. (L)