1. IntroductIon Medicinal plants have acquired immense popularity worldwide, resulting in a tremendous hike in consumption of herbal medicines. India, particularly the trans-Himalayan region, a habitat to thousands of useful medicinal plant species, has been a major part of India’s rich medicinal plant heritage. Physical features of these high altitude cold deserts include coarse and porous sandy soil prone to wind and water erosion; dense infux of ultraviolet and infrared radiations; lower oxygen levels; low atmospheric carbon dioxide; short cultivation seasons; prolonged freezing winters; temperature variations from 40 °C to - 40 °C; low relative humidity and negligible rainfall. Therefore, only those plant species which have adopted to adjust in such harsh climatic conditions can grow in these areas. Sikkim is reported to inherit nearly 424 species of medicinal plants, used in Ayurveda, Homeopathy, Siddha, Amchi, Unani and other folk medicines. With about 4,000 species and around 40,000 herbal formulations, 12 per cent of world’s medicinal plant requirement is supplied by India, 90 per cent of which are found in forest habitats 1 . With growing demand for plant based medicines, health products, pharmaceuticals, food supplements, cosmetics etc. in the national and international markets 2 . The urge to alternate artifcial antioxidants like butyl hydroxyl toluene, butyl hydroxyl anisole, gallic acid, etc. with naturally occurring antioxidants has increased because of the several negative health consequences 3 . Treeline ecotones are the transition zones between adjacent subalpine forest and open alpine tundra 4 . Shrestha 5 , et al., investigated the treeline dynamics of two environmentally contrasting areas of Himalayas in Nepal and discovered that in spite of varying climate, environment, tree species and seasonal climate changes, the treeline dynamics were similar. A team of experts including agronomists (improved cultivation technology), conservation campaigners (sway public for conservation), ecologist (plant growth ecosystem), enthobotanist (identifcation of plant), health policy-maker (includes conservation and utilisation of plants in policy and planning), horticulturist (cultivation of medicinal plant), legal experts (effective legal mechanism to ensure collection sustainable medicinal plants), park manager (conservation of plants within park and reserve vicinity), park planner (maintaining maximum diversity of medicinal plants in the park and reserve), pharmacogenosist (application of medicinal plants), plant breeder (breed improved strains of medicinal plants), plant genetic resource specialist (assessing and mapping of genetic variation in medicinal plants and maintenance of seed banks), plant pathologist (protection of cultivated medicinal plants from pests and diseases), religious leader (promotion of respect for nature), resource economist (evaluation of patterns of used and economic value of medicinal plants), seed biologist (germination and storage requirement of seeds), taxonomist (accurate identifcation of plant) and traditional health practitioner (informs about the use and availability of medicinal plants) 6,7 . Medicinal Plant Growing under Sub-optimal conditions in trans-Himalaya region at High Altitude Pooja Bhadrecha ! , Vivek Kumar #,* , and Manoj Kumar # ! Department of Biotechnology, Lovely Professional University, Jalandhar - 144 411, India # Amity Institute of Microbial Technology, Amity University, Noida - 201 313, India * Email: vivekbps@gmail.com AbStrAct Supporting people’s culture, income and healthcare, medicinal plants are of a great importance in Himalayas. Trading these herbal formulations worldwide is earning billions. But since the demand of such splendid plant and plant products has tremendously hiked in past two decades, and because of the unstable environmental changes due to global warming and industrialisation, these signifcant species are in threat of extinction. To preserve these treasures, several technical steps have been adopted by the government. A successful establishment of plants sector will raise rural empowerment, boost international commerce and contribute to health of millions worldwide. Alongside highlighting the major medicinal plant species and their uses, this review also foregrounds traditional medicinal practitioners, regions of trans-Himalayas rich in medicinal plants, major threats to these plants, signifcant biomolecules and detection techniques, threats to these plants, and government bodies and their responsibilities for their conservation. Keywords: Amchi; Bio-diverse; Agronomist; Enthobotanist; Horticulturist; Plant pathologist; Taxonomist Received : 19 January 2017, Revised : 08 February 2017 Accepted : 13 February 2017, Online published : 28 March 2017 37 Defence Life Science Journal, Vol. 2, No. 1, January 2017, pp. 37-45, DOI : 10.14429/dlsj.2.11107  2017, DESIDOC