The aim of the research is comprehensive investigation of oil-yielding flax and the efficacy of resources used by different growing technologies. The study was conducted in dry steppe zone of Ukraine on the dark chestnut soils in 2009–2013. We studied moisture regime: without irrigation and sprinkler irrigation; mineral nutrition: without fertilizers, N45P30K30, N60P45K45, and N90P60K60; space between rows: 15 and 45 cm; seeding rate: 5, 6 and 7 million seeds per hectare. It is established that rainfed conditions provided the greatest yield of seeds 1.65 t/ha and straw 2.36 t/ha by applying mineral fertilizers N90P60K60, space between rows 15 cm, and seeding rate 6 million seeds per hectare; under irrigation, the maximal yield of seeds 2.16 t/ha and straw 3.19 t/ha was provided by the same factors and seeding rate 7 million seeds per hectare. The specified complex of management practice provides the least coefficient of water consumption (938 m³/t without irrigation and 1211 m³/t under irrigation). Simultaneously, the growing under irrigation was attended by increasing the coefficient of water consumption by 24.9 % in average. The greatest coefficient of water consumption (1652 m³/t) was obtained at natural background of nutrition and moistening at space between rows 45 cm and seeding rate 7 million seeds per hectare. The coefficient of irrigation efficiency (a ratio of the irrigation demand value to the crop yield) reaches maximal values at the background without irrigation due to applying N45P30K30, when this index decreases by 15.9 %; due to N60P45K45 – by 21.1 %; N90P60K60 – by 26.4 %. Enhancing nutritional background decreases payback of fertilizers by 3.7–17.0 % without irrigation and by 7.8–13.2 % under irrigation. Maximal payback of fertilizers is provided by applying N45P30K30 at the space between rows 15 cm (without irrigation – 2.76–2.86 kg per one kg of active compound of fertilizer and 3.33–3.71 kg per one kg of active compound of fertilizer – under irrigation).
Keywords: oil-yielding flax, irrigation, mineral nutrition, seeding rate, space between rows, straw of oil-yielding flax.
