Evaluation of chemical compound of latex, ecological and phenological characteristics of Sweet Ferula assa-foetida in habitats of Kerman province

Background and objectives: Ferula assa-foetida L. belong to Apiaceae (Umbelliferae) family is one of the most important medicinal plants of Iran that has anticonvulsant, regulating and anti-parasitic effects and is used in the treatment of laryngeal spasm, gastrointestinal diseases, asthma and so on. Due to the economic importance of this plant and its special place in the pharmaceutical industry, this study was conducted to identify the ecological, phenological and germination needs of sweet Ferula assafoetida seeds in order to revive it in three natural habitats of Kerman province including Ravar, Kerman and Kuhbanan. Methodology: In each sampling area, three 500 m long transects were considered, and in each transect 10 randomly located 2´2 m2 plots were selected at 50 m intervals. Then density and percentage canopy cover were measured. In order to study phenology, 10 shrubs was randomly selected and marked in each habitat and germination time, leaf emergence time, Blooming time, seeding and drying time were recorded every 15-10 days. For measuring the soil properties of the habitat, several soil samples from 0 to 30 depth were collected and mixed and then one sample was transferred to the laboratory. To calculate the amount of rainfall we used Meteorological data of the north and northeast of Kerman province, which included the habitats of the sweet Ferula assa-foetida. Treatments included washed and cooled seeds and the control group. Sweet Ferula assa-foetida latex was prepared by water distillation by Clevenger. The Chemical compounds of the essential oil were identified using gas chromatography attached to a mass spectrometer. The data collected from the studied habitats were analyzed by SPSS 11.5 software and the means comparisons were done by Duncan multi-range test method. Results: In the studied habitats, the altitude range of Sweet Ferula assa-foetida varied between 1750-2100 m above sea level and its rainfall varied between 100-130 mm. The results of soil analysis revealed that this plant is not dependent on specific elements for growth and development. Soil has a sandy loam to clay loam texture and soil acidity ranged from 7.8 to 7.5. Electrical conductivity (EC) showed a significant difference and was varied from 0.7 in Kuhbanan pastureland to 2.30 in Ravar range pastureland. Soil organic matter was low and its amount was between 0.3-0.14 %. With increasing altitude in habitats, the average day and night temperature decreased and the temperature required to reach each stage of vegetative growth was delayed. The longest and shortest interval from emergence to autumn was in Kuhbanan habitat (2075 m) and in Ravar habitat (1750 m) respectively. Seed germination test showed that cooling and washing the seeds increased seed germination by 95.3% compared to control treatment. In general, 70 chemical compounds were identified in the essential oils of Ferula assa-foetida in the habitats. Conclusion: Considering that the same condition for selecting the samples, drying, extracting the essential oil and identifying its compounds were considered for all latex samples of sweet Ferula assa-foetida, severe fluctuations of its quality of chemical compounds can be caused by genetic or non-genetic changes in responding to ecological differences of habitats (ex. latitude and longitude, temperature, humidity and soil). Therefore, different climatic, edaphic and physiographic conditions of habitats affect the metabolic pathways and biosynthesis of active substances, and as a result, various secondary metabolites are biosynthesized under different environmental conditions.