Review on Ethnobotanical Plant Sources for Mosquito Repellency used by Tribes of South India

Mosquitoes have become a serious threat to public health, transmitting several dangerous diseases, especially in tropical regions. There has been a large increase in the insecticide resistance of this vector, and it has become a global problem. Carbon dioxide, lactic acid and many other odors released from the body of warm blooded animals are the major attracts of mosquitoes. Numbers of mosquito repellents are available in the market, both synthetic and natural. Depending on the type of phytochemical present, plant sources, acts as either repellent or as an insecticide for killing the larvae of mosquitoes. The repellent activity of plant sources has been explored by human beings for many years, and man started using these plant sources in different forms like burning of leaves, hanging the plant at the entrance, external application of oil from plant extracts or growing the mosquito repellent plants around the houses. The use of plant sources as active mosquito repellents was even recorded in the writings of Greek and Roman Scholars. In many parts of rural India and other parts of the world, plant based mosquito repellents are still in use. For eg: Plant sources, which have repellent activity, are preferred as a good and safe source by people in rural areas of Europe and North America. The plant sources, which were reviewed and found to be used as mosquito repellents by tribes of South India are Cymbopogon flexuosus, Ocimum americanum, Tinospora cordifolia (Willd.), Miers Pentanema indicum (Linn.), Ling Bixa Orellana L, eucalyptus globules and, Cassia fistula. These were used as topical application of leaf juice (or) essential oils, extracted from leaves and plant parts. Whereas, Adhatoda Vasica Euphorbia Milli Des. Azardiracta Indica A.Juss, Dalbergia sissoo DC, Vitex negundo Linn, Artimesia vulgaris L, Clausena anisata, Adhatoda Vasica and Anacardium Occidentale in different forms.