Сортовые особенности фотосинтетической активности овса посевного Тюменской селекции при внесении минеральных удобрений

Abstract

Abstract. The purpose is to study the varietal characteristics of the photosynthetic efficiency of oats when applying fertilizers in Western Siberia. Methods. The research was carried out on an experimental field located in the northern forest-steppe of the Trans-Urals. Photosynthetic potential and net productivity of photosynthesis were determined by the Nichiporovich’s method. Results. The nature of the formation of the assimilation surface and the accumulation of biomass of oat varieties Otrada, Talisman and Foma at different levels of mineral nutrition was studied. The photosynthetic potential and the net productivity of photosynthesis are calculated. The share of the influence of weather conditions, agrophone and variety on the studied indicators is determined. The Foma variety was characterized by maximum leafiness, compared to the Talisman and Otrada. On a natural agrophone, its assimilation surface in the sweeping phase reached 36.0 ± 5.5 thousand m2, at Otrada and Talisman – 28.1 and 24.0 thousand m2 per 1 ha of sowing. A very strong variability of the leaf surface area in Otrada was revealed (Cv = 24 %). The use of mineral fertilizers enhances the development of the leaf apparatus by 44–50 % and causes competition between oat plants. A close positive correlation was revealed between the leaf area in the sweeping phase and yield (r = 0.72). The area of the assimilation surface of oats is affected by: weather conditions – 37 %; nutrition level – 30 % and variety – 25 %. It was found that the Otrada and Foma varieties have the same accumulation dynamics and form the maximum photosynthetic biomass by the sweeping phase. The nature of biomass accumulation depends on weather conditions by 39 %; on mineral fertilizers by 29 % and on the genotype of the variety by 17 %. The productivity of the studied varieties is formed by increasing the assimilation surface, rather than increasing the efficiency of photosynthesis. Scientific novelty. For the first time, the photosynthetic potential was determined and the efficiency of the net photosynthesis productivity of oat varieties of the Tyumen selection was revealed. The share of the influence of various factors in the formation of the oat crop in the conditions of the Northern Trans-Urals has been established.