Abstract
Fennel (Foeniculum vulgare Mill.), a valuable essential oil plant, is cultivated mainly in the south of Russia. A comparative analysis of productivity parameters and biochemical indicators of 'Mertsishor' and 'Oksamit Cryma' fennel cultivars bred by the Research Institute of Agriculture of Crimea was conducted in the conditions of the Crimean piedmont and Belgorod region from 2022 to 2024. The aim of the research was to investigate prospects of fennel cultivation in Belgorod region. Analysis of main indicators was carried out according to the developed methodologies in a small-plot experiment (plots were three-row, row length – 5 m, row spacing width – 0.7 m, plot area – 9 m², with three replications). On average over the years of the research the yield of the 'Mertsishor' and 'Oksamit Cryma' cultivars in the first year of vegetation was significantly lower under conditions of Belgorod region (0.22–0.28 t/ha) than in the piedmont zone of Crimea (0.55–0.42 t/ha, respectively). Average essential oil content in fruits of both cultivars in most cases did not differ significantly between regions, nor did content of the main essential oil components – anethole (68.1–71.5 %) and fenchone (11.7–15.6 %) which meets requirements of GOST 3902-82. However essential oil yield of the 'Oksamit Cryma' and 'Mertsishor' cultivars was significantly lower (1.6 and 2.9 times, respectively, P ≤ 0.05) in Belgorod region (12.8–15.2 kg/ha). Comparative data on productivity of the second-year plants across two ecological locations could only be obtained for a single test year as plants in the Belgorod region perished during winter of 2022-2023. Fruit yield of the studied cultivars in 2024 (0.51–0.72 t/ha in the Crimean piedmont and 0.90–0.92 t/ha in Belgorod region) as well as essential oil yield (31.6–38.5 and 44.4–51.6 kg/ha, respectively) were higher in two-year-old plants. Results of the ecological trials for these fennel cultivars do not support their recommendation for cultivation in Belgorod region due to a high probability of plant loss during winter and low first-year productivity