Physiological potential of soybean seeds subjected to industrial treatment and storage time

Abstract

The use of treated seeds is a common practice among soybean producers, as it provides protection against pests and diseases existing in the soil, preventing their spread in exempt areas. Therefore, chemical treatment combined with different products becomes essential to guarantee success in the field.The objective of this study was to assess the influence that 7 industrial seed treatments (ISTs) and their respective slurry volumes have on the physiological potential of soybean seeds. The assay was carried out in a completely randomized design with 4 replications, with the treatments being arranged in a 7x6 factorial scheme (industrial treatments x storage periods). The chemical treatments were: control (untreated seeds) (ST1), fungicide + insecticide-1 + drying powder (ST2), fungicide + insecticide-1 + drying powder + micronutrient (ST3), fungicide + insecticide-1 + drying powder + micronutrient + biostimulant (ST4), fungicide + insecticide-1 + polymer + drying powder + insecticide-2 (ST5), fungicide + insecticide-1 + polymer + drying powder + insecticide-2 + micronutrient (ST6), fungicide + insecticide-1 + polymer + drying powder + insecticide-2 + micronutrient + biostimulant (ST7). For each IST, the specific slurry volume was 0, 350, 550, 1050, 500, 700 and 1200 mL 100 kg-1 of seeds, respectively. The seeds were stored for periods of 0, 15, 30, 45, 60 and 90 days and subsequently checked for their physiological potential. In each storage period, the following tests were conducted: germination, first count, accelerated aging, emergence speed index, and final emergence in sand substrate. Among the evaluated treatments, ST4 and ST7 were the most harmful to the physiological quality of the seeds in all storage periods, since they presented the greatest slurry volume. In relation to treatments with less harmful effects on seeds, treatments ST2 and ST3 presented higher averages for most of the variables analyzed