Effects of Macronutrients on the Growth, Essential Oil Production and Quality of Echinophora platyloba (DC.) in Natural Ecosystems

Echinophora platyloba DC. (Apiaceae) is recognized for its important secondary metabolites and antifungal agents. To evaluate the effects of macronutrient fertilizers on the growth parameters and essential oils yield of E. platyloba, a study was conducted in 2018 at Shahrekord University, Iran. The treatments included the individual and combined application of nitrogen, phosphorus, and potassium, along with control groups. The results revealed that nitrogen application significantly influenced biomass accumulation in stems, leaves, and inflorescences, with phosphorus-treated plants showing a notable increase in leaf weight. Compared to a positive control, phosphorus increased the essential oil yield by 488%, while nitrogen enhanced biomass accumulation by 165%. The primary compounds identified included (E)-β-ocimene, (E)-sesquilavandolol, and β-pinene, with percentages ranging between 21.3–32.1%, 14.1–42.0%, and 2.0–8.8%, respectively. The levels of β-pinene, (E)-β-ocimene, γ-decalactone, and spathulenol were found to be higher in the phosphorus and potassium treatments than in nitrogen. In contrast, limonene, linalool, geraniol, and (E)-sesquilavandulol concentrations were greater in the nitrogen treatment compared with phosphorus and potassium treatments. In conclusion, phosphorus fertilization can substantially increase the essential oil yield in E. platyloba compared to other treatments, potentially enhancing production per unit area, which supports farmers’ income and helps prevent the degradation of this species in natural habitats.