The most common medicinal plants of Sistan (Sistan & Balouchestan province, Iran) and some ethnobotanical aspects
The uses of herbs to cure diseases have been common in folk medicine of Iran since the ancient times. In the present work, the most common medicinally important species used by local inhabitants of Sistan region in (south-east of Iran) were collected from various localities and identified by using related flora and comparison with herbaria specimens. This area is severely affected by arid and semi-arid climates with relatively poor vegetation. For each species botanical name, vernacular name, used part (s), popular medicinal usage, forms of preparation and application were also provided on the bases of ethnobotanical and folk beliefs in local culture. The essential oil content of some species is also determined by hydrodistillation method. Thirty species belonging to 22 families and 29 genera were recognized as the most common medicinal plants in the study area from which 2 species are cultivated (Eucalyptus camaldulensis Dehnh. and Aloe vera L.), while the others grow as wild species. Also, only 2 species are monocotyledons and the others are dicotyledons. Some of the most important medicinal plants such as Eucalyptus camaldulensis (4%), Cuminum cyminum L. (3.5%), Trachyspermum copticum Link (3%), Foeniculum vulgare L. (2%), Nigella sativa L. (1%), Mentha longifolia Huds. (1%) and Citrullus colocynthis (L.) Schrad. (0.75%) showed high quantity of essential oils (Table 1), while Peganum harmala L. had the least amount (0.015%). The life forms of these plants were also determined. These medicinal plants are used in traditional medicine as diuretic, stomach improver, wound healing agent, antipyretic, expectorant, etc.