Sunflower cultivation technology with strip tillage in the Ciscaucasian zone

The article presents research materials devoted to evaluating the technology of sunflower cultivation with strip basic soil cultivation using elements of Strip-till technology in comparison with the recommended one. The originality of the approach to the cultivation system, in comparison with the classic Strip-till technology, consists in preliminary surface stubble cultivation in two tracks, which retains productive moisture, provokes more intensive germination of weeds, and, accordingly, a more effective effect of subsequent spraying of the stubble with glyphosate. It was found that during the growing season of sunflower with abnormally harsh climatic conditions in 2020 (GTC = 0.07) the soil density in the flowering phase of sunflower was 1.30-1.32 g/cm 3 , with low moisture reserves in layer 0-100 cm both in spring (57 and 65 mm, respectively) and in bloom (5 and 16 mm, respectively). Applying the fractal dimension method with the calculation of the development index of the root system D , it was found that the harder the agrophysical parameters were during the period of plant development, the less intensively the roots developed: at GTC = 0.22, the D index with the recommended technology and Strip-till technology was 1.63 and 1.76 units respectively, and at GTK = 0.07 — 1.46 and 1.51 units. The low yield of sunflower is associated with a deficit of productive moisture in the summer-autumn period of 2019 and 2020, with a lower reserve of 23 and 102 mm from the long-term norm; nevertheless, a significant increase in the yield of sunflower over the years of research was established by 0.96 and 0.14 tons/ha when cultivating a crop with strip tillage based on the introduction of elements of Strip-till technology in comparison with the recommended one, with a decrease in costs by 11% and an increase in profitability up to 136%.