Industrial treatment of soybean seeds subjected to high volumes of fungicides, insecticides, biostimulants and micronutrients during storage

The objective of this study was to examine the performance of soybean seeds at different storage periods as well as their physiological quality after the application of spray mixtures of insecticides, fungicides, polymers, micronutrients and biostimulants. The experiment was laid out in a completely randomized design with four replicates. Treatments were as follows: T1 - untreated seeds (control); T2 - insecticide and fungicide + polymer + drying powder; T3 - insecticide and fungicide + polymer + drying powder + micronutrient; and T4 - insecticide and fungicide + polymer + drying powder + micronutrient + biostimulant. For each industrial seed treatment (IST), the specific spray volumes tested were 0, 400, 600 or 1100 mL 100 kg seeds-1. Soybean seeds were stored for 0, 15, 30, 45, 60 and 90 days and subsequently evaluated for physiological potential. At each storage period, the following tests were conducted: germination, first count, accelerated aging, emergence speed index, final emergence in sand substrate, whole-seedling length, shoot length and root length. Industrial seed treatment reduces seed physiological quality. The seed treatment corresponding to the highest spray volume provided the lowest means in all tested treatments. For all analyzed variables, the ST4 treatment, to which biostimulant was added, presented the lowest averages, indicating that the greater the volume of spray, the greater the damage caused to the physiological quality of the seeds, both before and after storage