Influence of sowing density on agrobiological indicators and yield of spring barley (Hordeum Vulgare L.) in the Polissya region

Abstract

Spring barley (Hordeum vulgare L.) is an important food and industrial crop in Ukraine’s agricultural sector, espe- cially in the Polissya region. High demand for brewing-quality grain requires the use of effective agricultural technologies, among which seed sowing rate plays an important role. It determines plant density, competitive relationships in crops, and the level of realization of the genetic potential of the variety. Given the changing climatic conditions and product quality requirements, it is important to determine the optimal sowing rate for spring barley. Objective. To study the effect of different sowing rates on agrobiological indicators, yield, and protein content in spring barley (Hordeum vulgare L.) grain in the Polissya region of Ukraine and to determine the optimal sowing density. Methods. The research was conducted in 2024–2025 under production conditions at the Starodoroginske private enterprise in the Korosten district, Zhytomyr region. Three sowing rates were studied (3.5, 4.5, and 5.5 million viable seeds/ha). The indicators were analyzed by morphometric measurements, yield determination, and laboratory analysis of crude protein content. The data were processed statistically. Results. It was found that the sowing rate significantly affects the growth, yield, and quality of spring barley grain. The optimal rate was 4.5 million viable seeds/ha, at which the plant height was 73.6 cm, the yield was 3.2 t/ha, and the crude protein content was 11.3 %. This exceeded the indicators at rates of 3.5 and 5.5 million/ha, where growth and quality indicators deteriorated. Excessive thickening or sparse sowing caused competition or inefficient use of space, which negatively affected productivity. Conclusions. The application of a sowing rate of 4.5 million seeds/ha ensures balanced plant growth, efficient use of resources, and the formation of high-quality grain, which is optimal for the conditions of the Polissya zone and meets the requirements of the brewing industry.