Determination of the optimal pea seeding time under the conditions of the southern forest-steppe of the Omsk Region

Abstract

This paper discusses the research findings on the determination of the optimal sowing time for the Santana pea variety under the conditions of the southern forest-steppe of the Omsk Region on meadow-chernozem medium-thick low-humus soil over a period from 2021 through 2024. The sowing rate for peas was 1 million viable seeds per 1 ha; the preceding crop was spring wheat. At pea branching stage, the crops were sprayed with the herbicide Hermes OD - 0.8 L per ha with spray material consumption of 200 L ha. In the variants with fertilizer application, ammonium phosphate fertilizer (N₁₂P₅₂) was applied simultaneously with seeding with a La Rocca seeder to a depth of 5-7 cm. Germination density and survival of pea plants was higher in the variants with a sowing date of May 15 - 75.25% and 68.25%, respectively, with a weak influence of fertilizer. The maximum yield of pea grain against unfertilized background was obtained from crops of May 15 - 3.027 t ha; ammonium phosphate fertilizer application led a yield gain by 0.323 t ha. In earlier seeded crops, the grain yield against unfertilized background decreased to 2.965 t ha; fertilization with ammonium phosphate fertilizer provided additional 0.330 t of grain per 1 ha. Later seeding dates reduced the grain yield to 2.738 t ha, and the gains caused by ammonium phosphate fertilizer also decreased to 0.182 t ha. The minimum water consumption for obtaining 1 ton of pea seeds was obtained with the seeding date of May 15 and amounted to 870.2 and 798.2 tons against unfertilized and fertilized nutrition backgrounds respectively.