No abstract

Seed processing or conditioning is important for improving soybean seed lot quality as it improves the physical characteristics by eliminating inert materials, weed and non-standard seeds and increases physiological quality. The objective of this study was to evaluate the effect of processing on physical and physiological qualities of soybean seed, before and after each equipment and transport system, during processing in a Seed Processing Plant. Samples of six cultivars were obtained during processing while seeds passed through each machine, totaling fifteen sampling sites. The experimental design was entirely randomized, treatments arranged in 15 x 6 factorial scheme, with 10 replications. Characteristics evaluated were germination; vigor by accelerated aging test; tetrazolium test for viability (TZ 1 to 5), vigor (TZ 1 to 3), weathering damage (TZ 3), mechanical damages (TZ 2 to 8), stinkbug damages (TZ 2 to 8) and moisture content. Results showed that processing improves the physiological and physical qualities of soybean seeds and enhances average quality seeds. The equipment and the system of transport (lifts and conveyor belts) used in this study did not cause mechanical damages to the seeds; the mechanical damages were mostly detected in larger seeds and stinkbug damages were found in smaller seeds; and seeds with weathering damage were neither eliminated nor reduced by any processing line.

Seed processing machines remove viable seeds from non-viable seeds and inert materials based on physical characteristics. The objective of this study was to assess the effect of each processing machine alone on the physical and physiological qualities of the soybean seeds. Seed samples of two soybean cultivars - BMX Potência RR and NK 7059 RR - were collected from five machines separately: air-screen machine, spiral separator, size grader and gravity separator. The experimental design was a completely randomized factorial, varying with the equipment, with 20 replications. Samples were assessed by germination test, accelerated aging, viability and vigor by tetrazolium test (TZ), weathering damages (TZ class 3), mechanical damages (TZ 1-8) and (TZ 6-8), stink bug damages (TZ 1-8) and weight of one thousand seeds. The air-screen machine and the spiral separator did not contribute to improve physiological quality of seeds; the size grader concentrated mechanical damages in larger sizes and stink bug damages in smaller sizes. Gravity separators showed higher quality seeds at the upper part of the machine compared to intermediate and lower parts. Mechanical damages and stink bug damages can be reduced by gravity separator and weathering damages are not eliminated by any of the machines.