Effect of sowing density on grain yield, protein and oil content and plant morphology of soybean (Glycine max L. Merrill)

To find out exactly how sowing density and sowing pattern affect soybean grain yield, quality and its components in non-traditional soybean growing regions, such as Germany, two field trials have been conducted at two locations in Bavaria in 2016 and 2017. The experiments were carried out with four sowing densities (30, 50, 70, 90 seeds/m2) and four cultivars from different maturity groups (Viola 000, Lissabon 000, ES Mentor 00, Orion 00) as randomized complete block design with four replicates. Almost all evaluated traits varied significantly depending on year × location. There was no interaction between the main factors (cultivar × sowing density). The results revealed that grain yield and height of the first pod increased with increase of sowing density. The number of pods per plant and branching decreased with increasing sowing density. At higher sowing densities at flowering leaf area index was significantly higher than at lower sowing densities. The cv. ES Mentor (00) with 70 seeds/m2 has proved to be a suitable cultivar in terms of yield and quality in southern Germany (> 3.6 t/ha grain yield and 40% protein).