Response of Precision-Planted Soybean Morphology, Seed Quality and Yield to Varying Seeding Rates under Central European Conditions

In Central Europe, soybean is typically sown in narrow rows, whereas wide‑row precision planters offer more accurate within‑row spacing and greater flexibility for inter‑row cultivation and targeted applications. We evaluated whether soybean established with a 500‑mm precision planter responds to changes in seeding rate. A two‑year on‑farm strip trial (2023–2024) was conducted in Czechia with two determinate cultivars Satelia and Tertia in four target seeding rates (20, 40, 60, 80 germinating seeds/m²). Plant morphology, seed yield, and seed composition were assessed. Branch number (3.1–1 pcs/plant for Satelia; 2.4 – 1.1 pcs/plant for Tertia), pod number (54.2 – 22.6 pcs/plant for Satelia; 53.4 – 28.8 pcs/plant for Tertia), and fertile nodes (11.6 – 9.3 pcs/plant for Satelia; 12.2 – 9.7 pcs/plant for Tertia) all decreased linearly with increasing seeding rate in both tested cultivars, indicating strong morphological compensation at low plant densities. Seed yield dry mass and seed composition were not significantly affected by seeding rate within the tested range, while year and cultivar effects were more pronounced for several seed quality components. These results suggest that soybean yield and quality are largely buffered against variation in plant population.