Assessment of the weather conditions influence on the economic and value characteristics of Lavandula аngustifolia L. in the conditions of Kherson region

Assessment of the prospects of introduced and created varieties of Lavandula angustifolia L. in the conditions of the Southern Steppe in terms of yield and essential oil content in raw materials, as well as the influence of the weather conditions of the year on these economically valuable traits is given. The study included 11 samples of Lavandula angustifolia L. Ecological and phenological observations were carried out for the studied plants. During the period of mass flowering of plants, the crop was recorded. The mass fraction of the essential oil was determined by the Ginsberg method on the Clevenger apparatus. The main results of the multi-year research work on the assessment of collection samples for economic and valuable characteristics of Lavandula angustifolia depending on weather conditions are highlighted. On the basis of the State Enterprise «Experimental Farming “Novokakhov”» of the Institute of ClimateOriented Agriculture of the National Academy of Sciences of Ukraine, collection plots of narrow-leaved lavender samples were established for introductory study and testing in the conditions of the Southern Steppe. For 20 years in this region, Lavandula angustifolia underwent multi-vector study as an ornamental and essential oil crop.During this period, new variety samples and varieties adapted to local conditions were created, which have increased decorative indicators, as well as high yield and mass share of essential oil in raw materials. In particular, Lydia, Victoria and Sinieva Nadiyi varieties, with the following characteristics: plant height, cm — 65, 60.0 and 60.0, respectively; inflorescence length, cm — 8.0, 5.0 and 13.0; number of inflorescences on a plant, pcs. — 95, 230 and 200; number of flowers in an inflorescence, pcs. — 80, 49 and 90; essential oil content, % — 3.0, 3.8 and 3.25; collection of essential oil, kg/ha — 64.0, 83.0 and 71.0; content of linalyl acetate in essential oil, % — 48.0, 34.2 and 20.1; duration of the flowering period, days — 30; inflorescence yield, t/ha — 0.53, 0.55 and 0.55; frost resistance, score (1–9) — 9; resistance against pests, score (1–9): ant (Lasiusnsger) — 9; causative agents of diseases, score (1–9) — 9 — not detected (village Lidia), sora rot — 9 (village Victoria) and not detected (village Sinieva Nadiyi); zoning area — steppe. The period 2016–2021 is of particular interest, considering the study of the adaptability of culture. The weather conditions in the mentioned years differed among themselves in terms of temperature, amount of precipitation and their distribution, etc. Such conditions made it possible to assess comprehensively the influence of the weather conditions on the manifestation of economic and valuable characteristics of collections of lavender samples in this region, including newly created varieties of this valuable culture. Observations revealed deviations in the passage of phenological phases and the accumulation of essential oil. The minimum yields and essential oil content of all samples occurred in 2016, which is associated with a sharp drop in temperature and freezing of plant shoots. The maximum yield of raw materials was recorded in 2020, which is associated with the optimal amount of precipitation in the phase of growth and budding. The maximum indicators of the mass fraction of essential oil in raw materials were recorded in 2018, which is associated with high average daily temperatures and the absence of precipitation and dry weather during flowering. The results of the long-term evaluation of the samples of narrow-leaved lavender L. angustifolia based on the main economic and valuable characteristics indicate the prospects of industrial cultivation of the crop in the conditions of the Southern Steppe, and also convincingly prove the presence of genetic material of domestic origin adapted to the conditions of the region.