Potential capabilities of Psathyrostachys juncea during long-term use in the south of Central Siberia

The purpose of this research was to evaluate and select biotypes of Psathyrostachys juncea based on green mass productivity and feeding value during long-term study for grazing in the source nursery. Twenty-six accessions of Psathyrostachys juncea were studied in the source nursery for green mass productivity, plant height and vigor, and nutritional value during various simulated grazing cycles in the steppe zone of Khakassia from 2015 to 2024. The variety Manchaary was served as a control. The experimental plot soil was chestnut, with a light loamy texture. The hydrothermal coeffi cient according to G. T. Selyaninov for 2017–2024 ranged from 0.6 to 1.13, with an average hydrothermal coeffi cient value was 0.85. In the fi rst two years of life Psathyrostachys juncea developed mainly the root system, and on the surface it forms a weak rosette of shortened shoots. It is recommended to begin grazing animals on wild ruttishness pastures no earlier than the third year of life after sowing. In the third to fi fth years of life, the height of plants after three to four cuttings did not vary signifi cantly (27.88–30.69 cm), which was confi rmed by the low degree of its variability. For 2019–2021, in terms of the sum of cuttings the highest yield of green mass was noted for samples K 1, K 2, K 3, K 5, K 6 from 1310 to 1715 g/bush. The grass stand thickness for these samples was 3.5–4.0 points. The number of productive shoots per 1 plant was 319–550 pcs. After two cuttings, all varieties exceeded the standard in terms of the content of feed units per 1 kg of feed. In 2022, two cuttings were carried out in 2023–2024 one in each.