Effect of altitude on morphological diversity and essential oil constitutes of Prangos ferulacea (L.) Lindl.

Jashir (Prangos spp.) is forage, medicinal and indigenous herb from some parts of Iran that is used in traditional medicine in the treatment of many diseases. This study was conducted to investigate the effect of altitude on morphological traits and essential oil compounds of Prangos ferulacea (L.) Lindl. at the flowering stage in Kohgiluyeh and Boyer-Ahmad province, Iran. For this purpose, 10 plants were selected from each of three altitudes (2000-1600, 2400-2000 and 2800-2400 m above sea level). Measurements were made for 30 morphological traits and essential oil content and compositions of the plants in each altitude. Result of one-way ANOVA showed a significant difference among altitudes classes (p < /em><0.01) for most of traits. The results showed that with increasing altitude, the number of branches, the number of leaves per plant and the number of primary leaflets decreased and the number of umbrellas per plant, leaf length, internode length, fresh and dry weight of plant increased. Significant correlations were observed between some important morphological traits such as (leaf number and umbrellas number, leaf length, internode length, fresh and dry weights) with the essential oil content. Path coefficients analysis of morphological traits showed that altitude had the greatest effect on the canopy diameter (P = 0.733) and leaf width (P= 0.857). In total, 22 compounds of essential oil were identified in three different altitude classes. The major compounds were Δ-3-carene, α-pinene, (Z)-β-ocimene, myrcene, β-phellandrene, and α-terpinolene. Altitude had a negative effect on the essential oil yield. Overall, the results of this study showed that the many of the studied traits in P. ferulacea were strongly affected by altitude and there were significant differences among the three altitude classes. Finally, the observed diversity can be related to the role of altitude and the genetic structure of the populations, which can also be considered as a kind of adaptation and physiological response of Jashir to environmental conditions.