Sorting of Switchgrass (Panicum virgatum L.) seeds by a set of signs

The article presents the research results on the efficiency of switchgrass seeds sorting by a set of characteristics – specifc gravity and aerodynamic properties in order to reduce the biological state of seeds dormancy and germination increase signifcantly. It is experimentally proved that sequential seeds sorting in two stages by a set of features – specifc weight on the pneumatic table and aerodynamic properties on the aspiration column provided a signifcant increase in its germination energy, germination and 1000 seeds weight. Sorting of Morozko variety seeds on the pneumatic table ensured obtaining seeds with germination energy and similarity in positions 1 and 2, respectively – 16–19 % and 20–22 %, while in positions 3–5 these indicators were, respectively – 5–13 % and 9–17 %. Re-sorting of these seeds by aerodynamic properties provided an increase in germination energy and seed similarity from the position of the pneumatic table "3", respectively – by 12 and 13 %, the intermediate fraction – by 14–16 %, and waste – by 19–21 % compared to these indicators to sorting, due to the selection of the lung and with lower seed similarity. Sorting seeds by a set of characteristics provided not only an increase in its quality, but also an increase in the yield of more similar seeds. The most effective way to prepare switchgrass seeds for sowing is to sort them by a set of features – specifc weight and aerodynamic properties, which reduces the biological dormancy of seeds, signifcantly increases its germination energy, similarity, 1000 seeds weight and quality seeds. But this measure does not provide a complete solution to reduce the biological state of dormancy of seeds. Key words: seeds yield, aerodynamic properties, specifc gravity, germination energy, similarity, 1000 seeds weight.