Eleusine coracana, or finger millet, also known as ragi in India, kodo in Nepal, is an annual herbaceous plant widely grown as a cereal crop in the arid and semiarid areas in Africa and Asia. It is a tetraploid and self-pollinating species probably evolved from its wild relative Eleusine africana. Finger millet is native to the Ethiopian and Ugandan highlands. Interesting crop characteristics of finger millet are the ability to withstand cultivation at altitudes over 2000 m above sea level, its high drought tolerance, and the long storage time of the grains. History Finger millet originated in East Africa (Ethiopian and Ugandan highlands). It was claimed to have been found in an Indian archaeological site dated to 1800 BCE (Late Bronze Age); however, this was subsequently demonstrated to be incorrectly identified cleaned grains of hulled millets. The oldest record of finger millet comes from an archaeological site in Africa dating to the 8th century AD. By 1996, cultivation of finger millet in Africa was declining rapidly because of the large amount of labor it required, with farmers preferring to grow nutritionally-inferior but less labor-intensive crops such as maize, sorghum, and cassava. Such a decline was not seen in Asia, however. Taxonomy and botanical description of finger millet There are ten species under the genus Eleusine Gaertn, seven diploid (2n=16, 18 and 20) and three tetraploid taxa (2n=36 or 38). Eleusine africana (Kenn.-O'Bryne), Eleusine coracana (L.) Gaertn, Eleusine floccifolia (Spreng), Eleusine indica (L.) Gaertn, Eleusine intermedia (Chiov.) (S.M.Phillips), Eleusine jaegeri (Pilg.), Eleusine kigeziensis (S.M.Phillips), Eleusine multiflora (Hochst. ex A.Rich), Eleusine semisterilis (S.M.Phillips) and Eleusine tristachya (Lam.) Lam. Different studies confirmed that Eleusine coracana was originated from E. indica and E. floccifolia genomes and selected for cultivation from its wild type E. Africana. Growing regions Main cultivation areas are parts of eastern and southern Africaparticularly Uganda, Kenya, the Democratic Republic of the Congo, Zimbabwe, Zambia, Malawi, and Tanzaniaand parts of India and Nepal. It is also grown in southern Sudan and "as far south" in Africa as Mozambique. Climate requirements Finger millet is a short-day plant with a growing optimum 12 hours of daylight for most varieties. Its main growing area ranges from 20°N to 20°S, meaning mainly the semiarid to arid tropics. Nevertheless, finger millet is found to be grown at 30°N in the Himalaya region (India and Nepal). It is generally considered as a drought-tolerant crop, but compared with other