Bio Geographic Zones of India Current Affairs - 2020
According to the first comprehensive census of orchids of India titled ‘Orchids of India: A Pictorial Guide’, India is home to 1,256 species of orchid. The census containing photographs of 775 species is published recently by the Botanical Survey of India (BSI) was unveiled in early July 2019 Union Ministry of Environment, Forest and Climate Change (MoEFCC).
In the light of importance of orchids in floriculture, this publication by BSI, which has photographs of 60% of all species, is 1st authentic inventory and thus will be useful for researchers, growers, nature lovers and people with different backgrounds.
Key Findings of Study
1,256 orchid species or taxa belong are found in India.
388 species of orchids are endemic to India. Out of the 388 species about one-third (128) endemic species are found in Western Ghats.
Three life forms: Orchids can be broadly categorised into 3 life forms-
Epiphytic– are plants growing on another plants including those growing on rock boulders and often termed lithophyte. About 60% of all orchids found in India, which is 757 species, are epiphytic. These are abundant up to 1800 m (above sea level) and their occurrence decreases with increase in altitude
Terrestrial– are plants growing on land and climbers. 447 species in India are terrestrial. These grow directly on soil, are found in large numbers in temperate and alpine region.
Mycoheterotrophic– are plants which derive nutrients from mycorrhizal fungi that are attached to the roots of a vascular plant). 43 species in India are mycoheterotrophic. These are mostly associated with ectomycorrhizal fungi, are found in temperate regions, or are found growing with parasites in tropical regions.
Distribution of orchid:
Among 10 Bio Geographic Zones of India, Himalayan zone is richest in terms of orchid species followed by Northeast India, Western Ghats, Deccan plateau and Andaman & Nicobar (A&N) Islands.
North-East India rank at top in species concentration of Orchids.
Western Ghats have high endemism of orchids.
Highest number of orchid species: is recorded from Arunachal Pradesh with 612 species. This is followed by Sikkim with 560 species and West Bengal.
The entire orchid family is listed under Appendix II of CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora). Thus any trade of wild orchid is banned globally.