~ 103 ~ International Journal of Herbal Medicine 2017; 5(6): 103-107 E-ISSN: 2321-2187 P-ISSN: 2394-0514 IJHM 2017; 5(6): 103-107 Received: 18-09-2017 Accepted: 19-10-2017 Samydurai Ponnusamy Department of Botany, School of life Sciences, Bharathiar University, Coimbatore, Tamil Nadu, India Rajendran Arumugam Department of Botany, School of life Sciences, Bharathiar University, Coimbatore, Tamil Nadu, India Sarvalingam Ariyan Department of Botany, Sri Kaliswari College (Autonomous), Sivakasi, Tamil Nadu, India Rajasekar Chinnaiyan Department of Botany, School of life Sciences, Bharathiar University, Coimbatore, Tamil Nadu, India Correspondence Samydurai Ponnusamy Department of Botany, School of life Sciences, Bharathiar University, Coimbatore, Tamil Nadu, India Ethnobotanical knowledge of threatened plant species Andrographis in Nilgiris biosphere reserve, Tamil Nadu, India Samydurai Ponnusamy, Rajendran Arumugam, Sarvalingam Ariyan and Rajasekar Chinnaiyan Abstract Andrographis Wall ex Nees, is a large genus of herbs with greater species diversity occurring in the southern Western Ghats. Among the different species of Andrographis, the present study provides the ethnobotanical data of 9 rare, endemic/endangered species collected from the Nilgiris of the southern Western Ghats. The nine species show narrow distributional range and are vulnerable to unsustainable utilization. This study provided data on diversity, distribution and habitats for conservation and prioritization of the valuable species. Keywords: Andrographis species, diversity, distribution, Nilgiris, Ethnobotany 1. Introduction Traditional systems of medicine such as Ayurveda, Homeopathy are gaining popularity and interest throughout the globe due to their approaches in preventive and therapeutic measures [1] . Despite the availability of complicated, innovative developments of technology and modern medicine, traditional practices are still having prime importance for treating various diseases worldwide including India [2] . An estimated, 350 million of the world’s people depend almost entirely for their sustenance and daily needs on forests. In rural India around 200 milloin people are particularly depend on forest resources for their livelihood [3] . The Western Ghats of India, known for its rich species diversity and endemism. It is home to a great variety of ethno-medicinally important plant species, and is ranked sixth among twelve mega diversity countries of the World [4] . The interest in biodynamic phytotherapy has increased many folds all over the world because of impressive record of safety and efficacy for many common diseases and several chronic ailments [5] . The ethnic medicinal plants are of great significance to the health of individuals, ethnic communities and traditional healer for demand of medicinal plants has increased numerous folds in the therapeutic remedies of various ailments due to active phytoconstituents [6] . The Andrographis is a large genus of family Acanthaceae [7] . About 21 species of Andrographis are reported to occur in India [8, 9, 10] . On hilly habitats nearly all the plants of a species flower as a rule in the same season [11] . Species of the genus Andrographis have been used in local folklore medicine for a wide variety of diseases such as fever, malaria, diarrhea, cough, muscular pains and used for the expulsion of worms, in the tribal and rural communities. Many pharmacological studies have been conducted as an attempt to authenticate its use as a multipurpose medicinal agent [12, 13, 14] . As far as threatened species of Andrographis of the Western Ghats are concerned, no detailed inventory was undertaken in the past. In the past few years some reports have been appeared on the floristic studies of Nilgiris Biosphere Reserve [15, 16, 17, 18] . Some of the species may be lost without gaining any attention. Since most of the threatened species in NBR, Western Ghats are located near the human settlements, human disturbance in these forest are progressively increasing [19, 20] . In view of the above facets, the present study was conducted to identify the threatened plant taxa of Andrographis in Nilgiri’s Biosphere Reserve forest. 2. Materials and Methods 2.1 Study area The Western Ghats of Nilgiri’s, one of the 34 globally recognized biodiversity hotspot also forms a significant part of the state area of 2,479 square kilometres (957 sq mi) the mountains central location is 11°22ƍ30ƎN 76°45ƍ30ƎE [21, 22] . In fact, Tamil Nadu is the only state where both the hill ranges of Western Ghats and Eastern Ghats, meet at the Nilgiri hills exhibits great