The aim of the research was to study the dynamics of available water and main nutrients for sunflower depending on growing technologies and their influence on the crop productivity at the background of insufficient moisturizing in the Rostov region. Factors studied were: growing technology (extensive (without fertilization), normal (applying of ammophos by the norm of 150 kg/ha), intensive (applying of ammophos by the norm of 300 kg/ha), biologizing (applying of organic-mineral fertilizer “Agrovit-Kor” by the norm of 300 kg/h); primary soil cultivation (tillage to the depth of 27–30 cm, combined to the depth of 16–18 cm, surface to the depth of 8–10 cm); cultivar [Jazzy F1, R 453 (Rodnik)]. It is established that the best soil water regime to the harvest of sunflower was at the tillage. In this variant the stock of available water in topsoil was 44.0 mm against 39.6 mm at combined cultivation and 37.4 mm at surface one. The use of mineral fertilizers in normal and intensive technologies, as well as applying of organic-mineral fertilizer “Agrovit-Kor” in biologizing technology, increased the content of main nutrients by 15–20 % comparing to the extensive technology, what improved the conditions for growth and development of sunflower plants. Maximal seed yield of sunflower cultivar Jazzy F1 (2.41 t/ha) and cultivar Rodnik (2.0 t/ha) was obtained by growing at intensive technology using tillage as primary soil cultivation. In this variant the greatest yield of oil per one hectare was marked, the yield was 1048 and 857 kg respectively.
Keywords: soil moisture, available water, nitrate nitrogen, labile phosphorus, exchangeable potassium, yield, seed quality.
