Evaluation of new determinant soybean varieties in the Central Black Earth zone of the Russian Federation (on the example of the Orel region)

The research was carried out in LLC NPO ‘Betagran Seeds’ in 2023-2024. The soil of the experimental field is dark grey forest medium loamy medium cultivated. Soil acidity pH is 5.7, humus content is from 5.25% to 5.5%. The arable layer is highly provided with mobile phosphorus and potassium (187 and 174 mg/kg, respectively). The sum of absorbed bases is 32.7 mg-eq/100 g. Soybean was preceded by winter wheat. Sowing was carried out in the second decade of May with a planter Klyon-2.8 + MTZ-80.2. The repetition was three times, the accounting plot area was 20.1 m2. The sowing method was wide-row sowing with row spacing of 45 cm. The seed sowing rate was 600 thousand/ha, the seeding depth was 3-5 cm. Harvesting was carried out with a ZÜRN 110 combine harvester. The calculation was made in terms of standard moisture content (14%) and 100% grain purity. In all variants of the experiment in autumn potassium sulphate 150 kg/ha and ammophos 300 kg/ha were applied, in spring - 150 kg/ha of ammonium sulphate and before sowing 50 kg/ha of ammophos. Seeds were treated with fungicide Heracleon, 1.2 litres/t and insecticide Imidor PRO, 2 litres/t before sowing. The objects of research were two new determinant early maturing soybean varieties selected by JSC ‘Shchelkovo Agrochem’ D-82, D-22 (in the process of transfer to the GSI) and Lancetnaya variety as a control. The experiment variants were three cultivation technologies of different intensity: technology 1 - control - it included a complex of pesticides for protection against pathogens, pests and weeds; technology 2 - control + fertilization with nitrogen, sulphur and potassium; technology 3 - control + growth stimulants + macro- and microelements fertilization. It was found that the new varieties D-82 and D-22 on the duration of the growing season differed from the control variety Lantsetnaya in greater stability and lower rate of reaction to the dynamics of average daily temperatures and precipitation. The studied cultivation technologies did not affect the phenophases of development of the studied soybean varieties. In both years of research under all cultivation technologies, the new soybean varieties exceeded the control variety Lantsetnaya in yield significantly.