The genus Rhododendron of Indian Himalayan Region (IHR) has been enumerated in the present paper. A total of 87 species, 12 subspecies and 8 varieties of Rhododendrons recorded in IHR, among these 6 species and one subspecies are reported from Western Himalaya. The maximum concentration of 86% observed in Arunachal Pradesh (75 species). The species of Rhododendrons exhibit significant diversity in habit and broad range of distribution from the altitude of 800-6000 m. and the best range is observed in 3001-3500 m altitudes. In analysis revealed 20 taxa are endemic, 30 are rare, 24 are threatened / endangered, 3 are vulnerable and 47 taxa have to be assessed. The major threats to rhododendrons are deforestation and unsustainable extraction for firewood and incense by local people has been discussed.
C. Linnaeus, “Species Plantarum,” Vol. 1, London, 1753, pp. 392.
D. J. Mabberley, “Mabberley’s Plant-Book. A Portable Dictionary of Plants, Their Classifications and Uses,” 2nd Edition, Cambridge University Press, Cambridge, 2008.
U. C. Pradhan, “A Preliminary enumeration of Rhododendrons of the Indian region—Part 1,” Himalayan Plant Journal, Vol. 3, No. 8, 1985, pp. 110-123.
J. Cullen, “A Revision of Rhododendron. I. Subgenus Rhododendron Sections Rhododendron and Pogonanthum,” Notes from the Royal Botanic Garden Edinburgh Vol. 39, 1980, pp. 1-207.
D. F. Chamberlain, “A Revision of Rhododendron II. Subgenus Hymenanthes,” Notes from the Royal Botanic Garden Edinburgh, Vol. 39, 1982, pp. 209-486.
W. R. Philipson and M. N. Philipson, “A Revision of Rhododendron III. Subgenera Azaleastrum, Mumeazalea, Candidastrum and Therorhodion,” Notes from the Royal Botanic Garden Edinburgh, Vol. 44, 1986, pp. 1-23.
D.F. Chamberlain and S. J. Rae, “A revision of Rhododendron IV. Subgenus Tsutsusi,” Edinburgh Journal of Botany, Vol. 47, 1990, pp. 89-200.
K. A. Kron, “A Revision of Rhododendron Section Pentanthera,” Edinburgh Journal of Botany, Vol. 50, 1993, pp. 249-364.
W. S. Judd and K. A. Kron, “A Revision of Rhododendron VI. Subgenus Pentanthera (Sections Sciadorhodion, Rhodora, and Viscidula),” Edinburgh Journal of Botany, Vol. 52, 1995, pp. 1-54.
U.C. Pradhan, “A Preliminary Enumeration of Rhododendrons of the Indian region—Part 2,” Himalayan Plant Journal, Vol. 4, No. 11-12, 1986, pp. 73-76.
R.B. Ghosh and U.P. Samaddar, “The Rhododendrons of the North-East India,” Journal of Economic and Taxonomic Botany, Vol. 13, No. 1, 1989, pp. 205-220.
D. Bhattacharyya and M. Sanjappa, “Rhododendrons Habitats in India,” Journal of American Rhododendron Society Vol. 62, No. 1, 2008, pp. 14-18.
A. R. K. Sastry and P.K. Hajra, “Rare and endemic species of Rhododendrons in India—A Preliminary Study,” In: S. K. Jain and R. R. Rao, Eds., An Assessment of Threatened Plants of India, BSI, Calcutta, 1983, pp. 222-231.
A. A. Mao, K. P. Singh and P. K. Hajra, “Rhododendrons,” In: N. P. Singh and D. K. Singh, Eds., Floristic Diversity and Conservation Strategies in India, BSI, Calcutta, 2002, pp. 2167-2202.
U. C. Pradhan and S. T. Lachungpa, “Sikkim Himalayan Rhododendrons,” Primulaceae Books, Kalimpong, 1990.
K. K. Singh, S. Kumar, L. K. Rai and A. P. Krishna, “Rhododendron Conservation in Sikkim Himalaya,” Current Science, Vol. 85, 2003, pp. 602-606.
J. Y. Yumnam, “Rhododendrons in Meghalaya Need Attention,” Current Science, Vol. 95, No. 7, 2008, pp. 817-818.
D. K. Singh and P. K. Hajra, “Floristic Diversity,” In: G. S. Gujral and V. Sharma, Eds., Changing Perspectives of Biodiversity Status in the Himalaya, British Council, New Delhi, 1996.
S. S. Samant, U. Dhar and L. M. S. Palni, “Medicinal Plants of Indian Himalaya: Diversity Distribution Potential Values,” Gyanodaya Prakashan, Nainitial, 1998.
N. P. Singh, J. R. Sharma, K. P. Singh and V. Mudgal, “Species Diversity in Angiosperms,” In: N. P. Singh and D. K. Singh, Eds., Floristic Diversity and Conservation Strategies in India, Botanical Survey of India, Kolkata, Vol. 5, 2002, pp. 1631-1674.
Anonymous, “IUCN Red List of Threatened Species,” Version 2009.2. http://www.iucnrelist.org/
F. Mingyuan, F. Ruizheng, H. Mingyou, H. Linzhen, Y. Hanbi and D. F. Chamberlain, “Rhododendron,” In: W. Zhengyi, P. H. Raven and H. Deyuan, Eds., Flora of China, Science Press, Beijing and Missouri Botanical Garden Press, St. Louis. 2005, Vol. 14, pp. 260-455.
P. Thakur, Y. D. Sharma, B. Kashyap and A. Thakur, “Vegetative propagation of native ornamentals of Himachal Pradesh in India,” Abstract of XXVII International Horticultural Congress—IHC2006, Himachal Pradesh, 2006.
K. K. Singh, S. Kumar and R. Shanti, “Raising Planting Materials of Sikkim Himalayan Rhododendron through Vegetative Propagation Using Air-Wet Technique,” Journal of American Rhododendron Society, Vol. 62, 2008, pp. 136-138.
K. K. Singh, and B. Gurung, “In vitro Propagation of R. maddeni Hook. f. an Endangered Rhododendron Species of Sikkim Himalaya,” Notulae Botanicae Horti Agrobotanici Cluj-Napoca, Vol. 37, No. 1, 2009, pp. 79-83.
G. Lloyd and B. McCown, “Community-Feasible Micropropagation of Mountain Laurel, Kalmia latifolia, by Use of Shoot Tip Culture,” Proceedings of International Plant Propagation Society, Vol. 30, 1981, pp. 421-427.
W. C. Anderson, “A revised Medium for Shoot Proliferation of Rhododendron,” Journal of American Society & Horticultural Science, Vol. 109, 1984, pp. 343-347.
G. C. Douglas, “Propagation of Eight Cultivars of Rhododendron in vitro Using Agar-Solidified and Liquid Media and Direct Rooting of Shoots in vivo,” Scientia Horticulturae, Vol. 24, 1984, pp. 337-347.
B.H. McCown and G.B. Lloyd, “A Survey of the Response of Rhododendrons to in vitro Cultures,” Plant cell tissue and organ culture, Vol. 2, 1985, pp. 77-85.
B. A. Briggs, S. M. McCulloch and L. A. Caton, “In vitro propagation of Rhododendron,” Acta Horticulturae, Vol. 364, 1994, pp. 21-26.
P. W. Evers, J. Donkers, A. Prat and E. Vermeer, “Micropropagation of forest trees through tissue culture,” Centre for Agricultural Publishing and Documentation, Wageningen, 1988.
R. Almeida, S. Gon?alves and A. Romano, “In vitro Micropropagation of Endangered Rhododendron ponticum L. subsp. baeticum (Boissier & Reuter) Handel-Mazzetti,” Biodiversity and Conservation Vol. 14, No. 5, 2005, pp. 1059-1069.