Discussion
Different parts of medicinal plants were used as medicine by the local traditional healers. Among the different plant parts, the leaves were most frequently used for the treatment of diseases followed by whole plant parts, fruit, stem, root, stem and root bark, seed, flower and latex. The methods of preparation (Figure 3) fall into four categories, viz.: plant parts applied as a paste (38%), juice extracted from the fresh plant parts (24%), powder made from fresh or dried plant parts (20%), some fresh plant parts (6%), and decoction (12%). External applications (mostly for skin diseases, snake bites and wounds) and internal consumption of the preparations were involved in the treatment of diseases.
Figure 3  Method of preparation.
Figure 4  Number of remedies used for various ailments.   It was observed that, most of the remedies consisted of single plant part and more than one method of preparation. However, many of the remedies consisted of different parts of the same plant species to treat single or more diseases. For example, Andrographis paniculata – leaf paste is used to treat poison bites and leaf powder is used to treat diabetes; Gymnema sylvestre – root powder is used to treat poison bites and leaf powder is used to treat diabetes; Ricinus communis -juice extracted from leaves is used to increase secretion of milk and oil obtained from seeds is used to treat stomach ache; Azadirachta indica – leaf paste is used to treat small pox, rheumatism and skin diseases and young twigs are used as tooth brush; Ficus benghalensis – stem latex is used to treat heel cracks and young twigs are used as tooth brush; Moringa oleifera – boiled leaves are used to reduce body heat, to treat indigestion and eye diseases and flowers are used to cool the eyes and increase sperm production; Zizyphus mauritiana – decoction of leaf is used to get relief from body pain and bark powder is used to treat wounds; Solanum torvum – juice extracted from the leaf is used to reduce body heat and unripe fruits are used to strengthen the body.
Moreover a single plant is used for more than one disease. For example, Andrographis paniculata (diabetes and scorpion bites), Trianthema portulacastrum (constipation and asthma), Aerva lanata (cough, sore throat and wounds), Gymnema sylvestris (diabetes and poison bites), Wattakaka volubilis (rheumatic pain, cough, fever and severe cold), Sphaeranthus indicus (skin diseases and piles), Heliotropium indicum (wounds and skin affections), Cassia absus (wounds and skin affections), Cassia occidentalis (scabies and bone fractures), Terminalia arjuna (wounds, headache and tooth infections), Mukia maderaspatana (cold and cough), Cyperus rotundus (milk secretion and scorpion bites), Euphorbia hirta (wounds and lip cracks), Phyllanthus emblica (cold and cough), Ricinus communis (milk secretion ad stomachache), Clitoria ternatea (eye diseases and headache), Pongamia pinnata (wound and gas trouble), Coleus aromaticus (indigestion and cough),Leucas aspera (headache and fever), Ocimum sanctum (cough, cold and headache), Cinnamomum verum (cough, dysentery and body cooling), Aloe vera (hair loss and good sleep), Azadirachta indica (small pox, rheumatism and skin diseases), Moringa oleifera (body heat, indigestion, eye diseases and to increases sperm production), Syzygium cumini (swellings and body heat), Zizyphus mauritiana (body pain and wounds), Citrus aurantifolia (fever, headache and cold), Cardiospermum halicacabum (throat infection and headache), Solanum torvum (to reduce body heat and to strengthening the body), Solanum trilobatum (cough and itching) and vitex negundo (headache, fever, cold and cough) and these recipes are prepared using different ingredients of non-plant origin such as water, salt, honey, etc.
Common health problems in the sites of the study area were skin problems such as wounds, cuts, burns and skin diseases and the largest number of the remedies (wounds – 16 remedies and skin diseases – 9 remedies) was used to treat these troubles. Several studies have enumerated the plants used for wound healing and skin diseases in various parts of the world [14,32-34]. 24 remedies were used to alleviate problems of the respiratory system such as cold, cough and asthma. Most of the plants in Lamiaceae were used to treat cold, cough, fever, headache and asthma. Ghorbani [35] reported 16 plant species that were used for respiratory diseases in north Iran and safety and efficacy of the treatments for respiratory track infections were reviewed [36]. Common ailments such as headaches or coughs are considered to be diseases with natural causes and hence their symptoms are treated at the household level, without resource to magical practices [12]. In the present study eight remedies (Terminalia arjuna, Leucas aspera, Ocimum sanctum, Sida acuta, Citrus aurantifolia, Cardiospermum halicacabum, Lantana camara and Vitex negundo) were used to get relief from headache. Recently Ignacimuthu et al [37] reported that Ceropegia candelabrum, Pergularia daemia and Vitex negundo were used by tribals for the treatment of headache.
Traditional healers of Kancheepuram district used nine plant species to treat stomach problems (three plants to treat stomachache and six plants to cure digestive problems). In North-Western Patagonia the people of Curruhuinca community were affected with digestive problems and the highest fidelity level was found for species utilized for treating digestive ailments [38] and Ghorbani [35] reported that there were 48 plants for the treatment of gastrointestinal disorders in north of Iran. The tribal people of Western Madhya Pradesh of India used 13 plants for the treatment of jaundice [19]. In the present study only Phyllanthus amarus was used for the treatment of jaundice. Abutilon indicum, Azadirachta indica, Ficus benghalensis and Terminalia arjuna were used to treat dental problems. Various studies have reported on the indigenous use of medicinal plants in the treatment of oral diseases [[39] &[21]]. Andrographis paniculata, Catharanthus roseus and Gymnema sylvestre were used to treat diabetes by the local traditional healers. Chherti et al [15] reported that the tribal people of Sikkim and Darjeeling Himalayan region in India utilized 37 species of plants belonging to 28 different families as antidiabetic agents.