The Effect of Environmental Factorss on the Amount of Essential Oil of Nepeta asterotricha Rech.f. Using RDA Technique

Nepeta asterotricha Rech.f. is a medicine plant. The goal of this research is to investigate the effect of some environmental factors on amount of essential oil of Nepeta asterotricha Rech.f at 8 habitats in Yazd province to determine optimal environmental factors for rangeland management and reclamation. Soil samples were collected and measured phosphorus, nitrogen, and potassium and pH, electrical conductivity, and sand, silt, and clay (Hydrometric) at three replications from each habitat. Topographic factors including elevation, slop, and aspect were recorded in habitats. Plant samples in three replications in 8 habitat and essential oils were obtained by hydro distillation for 3 hours. Investigation on the correlation between essential oils and some ecological factors were done by using Redundancy Analysis v. 4. Comparison of means were done using Tukey tests (p≤ 0.05). Number of identified chemical compounds were 31 that 24 components had different between habitats. Results showed that the active ingredients in Nepeta asterotricha Rech.f including α-Thujene, α-Terpinene, p-Cymene, (Z) -β-Ocimene, γ-Terpinene, terpinen-4-ol, cis-Sabinene hydrate, α-Terpinolene, 4aβ, 7α, 7aα-nepetalactone and 4aα, 7α, 7aβ-nepetalactone had significant differences at 95% level in growing and flowering phases, and 8 habitats.The active substances of 1, 8-Cineole, cis-Sabinene hydrate, trans-Caryophyllene and Limonene had most of amount in the growing phase and the Rose furan epoxide, 4 aβ, 7α, 7aα-nepetalactone, α-Pinene, cis-Linalool oxide, α -Terpinolene in the flowering phase.Eelectrical conductivity, potassium, sand and elevation from sea level among environmental factors,had more effects in flowering phase. Scine, Thghiabad and Dehbala habitats had better situations of environmental factors and the essential oil are recommended to ude from the species of these habitats for reclamation of regions with similar environmental factors. Also these habitats were determined as the optimal habitats for this species in Yazd province.