Investigating the survival of medicinal-industrial plant Ferula assa-foetida L. in different exploitation methods, emphasizing the protection of this valuable plant

Background and purpose: The use of medicinal plants has grown greatly in developed countries, so that most of the world's population uses medicinal plants for primary health care. With the increasing demand of global markets, more attention is needed in the field of identifying and preserving medicinal plants. Not having enough knowledge about the sustainable exploitation of medicinal plants has put many of them at risk of extinction. Ferula assa-foetida is one of the endemic and medicinal species of Iran's rangeland, and the oleo-gum resin produced by it is one of the country's export products. According to the increase in the price of F. assa-foetida in recent years, unfortunately, the improper harvesting and oleo-resin of F. assa-foetida resin in terms of suitable age for exploitation have diminished. The number of annual harvests, as well as the method of exploitation, has reduced the density of F. assa-foetida plants in pastures, and the generation of this useful plant is at risk of extinction. Therefore, the purpose of the present study is to determine the best methods of exploitation for F. assa-foetida in order to continue its growth in natural areas.
Methodology: This research was carried out in Tangsarakh rangeland, Boyer-Ahmad County. After the detection of the region, areas were selected for the research, which were similar to each other in terms of slope percentage, vegetation, and soil appearance, and had a sufficient number of F. assa-foetida plants at different ages. The effect of cutting age factors (three treatments: 5-6 years old, 7-8 years old, and 9-10 years old), cutting method (three treatments: one-sided, two-sided, and traditional cutting methods), and cutting number (three treatments: cutting 10, 15, and 20 times) was checked with 10 repetitions on survival percentage. Also, at the end of the vegetative period in the second year, the morphological characteristics of F. assa-foetida were measured. Analysis of plant survival in different harvesting methods was done using the logistic regression method with SPSS software version 21.
Results: The results of logistic regression analysis showed that all treatments had a significant effect on the survival of the plant (p = 0.05). With increasing age of the plant, the survival rate decreases. At the ages of 5-6 years, 7-8 years, and 9-10 years, respectively, 51, 50, and 34 plant bases were regrown, and 39, 40, and 56 plant bases were lost. In one-sided and two-sided cutting methods, 71 and 64 plant bases re-grew, respectively, and in the traditional cutting method, no plant base re-grew. The results of the survival of F. assa-foetida in different numbers of cuts showed that in the treatments of 10, 15, and 20 times of cutting, 51, 44, and 40 plant bases were regrown and 39, 46, and 50 plant bases were lost. The mean leaf length was 39.88 cm, the mean leaf width was 12.77 cm, the mean leaf height was 36.88 cm, the mean number of leaves was 7.27, and the root diameter was 9.18 cm.
Conclusion: Considering that F. assa-foetida is an important endemic plant with high economic value, the livelihood of a large number of users depends on the product of this plant. Therefore, it is suggested to use the results of this research in the study area and other areas with similar ecological conditions to manage F. assa-foetida habitats.