The use of mineral fertilizers in sunflower crops in the conditions of Ryazan region

The most important direction of increasing the production of sunflower oilseeds is improvement of technology elements that provide a fuller use of the productivity potential in soil and climatic conditions of a particular region. In this regard, the aim of the research was to identify the varieties and hybrids of sunflower most adapted to the natural and climatic conditions of Ryazan region, accounting for different levels of mineral nutrition. In order to identify biological features and economically valuable traits, a field experiment was conducted in 2017–2019. Agrotechnical measures for the cultivation of sunflower were carried out in accordance with zonal recommendations. As a result of the studies, it was found that variety Poseidon 625 was the most adapted to the climatic conditions of Ryazan region. Sunflower plants of Poseidon 625 variety were noted to have the smallest height (158–172 cm), the largest leaf surface area (11.61–16.53 thousand m 2 /ha), the largest number of seeds formed in one basket (1,194–1,247 pcs), the largest mass of 1,000 seeds (49.9–59.8 g) and the highest yield (2.37–2.99 t/ha). On average, in 2017–2019, the introduction of full mineral nutrition in doses of N 125 P 60 K 60 and N 125 P 120 K 120 contributed to an increase in the yield of sunflower oil seeds by 0.06–0.45 and 0.07–0.62 t/ha, depending on the cultivated variety and hybrid.