Влияние основных приемов и способов возделывания ярового ячменя на площадь ассимиляционной поверхности и индекс листовой поверхности посевов в почвенно-климатических условиях Курской области

Abstract

Purpose: to determine the influence of the cultivar, seeding rate and application of mineral fertilizers when cultivating spring barley on the assimilation surface area of one plant and the leaf surface index of crops according to the crop growth phases in the soil and climatic conditions of Kursk region. Materials and methods. The studies were conducted in 2022 and 2023 in the field experience at Federal Agricultural Kursk Research Center in grain-fallow crop rotation. The experimental scheme includes the study of three cultivars – Suzdalets, Prometheus, Despina. The second factor is seeding rates: 3, 4, 5, 6 million units of viable seeds per 1 ha. The third factor is the levels of mineral fertilization: control without fertilizers and N₃₀P₃₀K₃₀. Results. It was found that the assimilation surface area of one spring barley plant in the seedling stage depended to a greater extent on the cultivar (by 40 %), and it also increased under the influence of mineral fertilization (by 16 %). The leaf area index of spring barley in the seedling stage depended by 89 % on the seeding rate. During the tillering stage, the leaf area depended by 72 % on the year conditions. Research during the crop blooming stage revealed that the main factor influencing the assimilation surface area and leaf area index was the year of study (31 and 44 %, respectively), the cultivar factor provided 23 and 27 % of the indicator variation, respectively, and the mineral fertilization – 20 and 30 %, respectively. During the milk-ripe stage, due to the leaves dying off, a decrease in the photosynthetic parameters of spring barley is observed. Conclusion. It has been determined that the assimilation surface area of one plant and the leaf area index are very dynamic indicators and largely depend on the year of research, the cultivar and the mineral fertilization. During the initial period of crop growth, the leaf area index is affected by the seed application rate.