Genetic diversity of Coelogyne nervosa A. Rich. was investigated by using SDS-PAGE, RAPD markers, and morphological characters. Coelogyne nervosa grows as epiphyte as well as lithophytes in Eastern and Western Ghats of India. Leaf samples collected from these two reference sites were taken for RAPD and protein profile analysis. Vegetative parts such as leaves, pseudobulbs, and roots were fixed in FAA. Free-hand and microtome sections were cut and stained with safranin-fastgreen. The objective of this study was to assess the genetic diversity of an endemic orchid, C. nervosa distributed in Southern India. The six populations collected from these two geographical regions exhibited significant variations in their morphological and molecular characters. The stomata were tetracytic and hypostomatic in distribution. The maximum thickness of cuticle and midrib region in leaf and extensive lignification in exodermis and endodermis of root were recorded in populations located in Western Ghats as compared to those of Eastern Ghats; it is interpreted to be associated with the conservation of water. RAPD and protein profile data showed the inter-population diversity between these two reference sites. This can be attributed to the ecological and climatic conditions prevailing in the Eastern and Western Ghats of India.
The present investigation deals with in vitro regeneration of an epiphytic orchid, Dendrobium aphyllum (Roxb.) C.E.C Fischer using leaf explants through Protocorm-like bodies (PLBs) proliferation. The species collected from the Darjeeling Himalaya (Latpanchar forest, Kurseong) has been classified as Least Concern by the IUCN Red List (2020). Ethnomedicinally, this plant has been used for curing skin disorders, scorpion bite, and wounds. Additional presence of 2,4-D/BAP (0.5, 1.0, 1.5, 2.0 mgl-1) in MS medium proved obligatory for inducing callusing in the leaf explants; callusing was however, highly promoted in the former combination. Further, the combination of both these additives showed synergistic effect in inducing better response. The growth and differentiation of callus tissues derived from leaf explants was further investigated on MS medium supplemented with different concentrations of 2,4-D and BAP. Optimal results were obtained on 2, 4-D (1.5 mgl-1) and BAP (1 mgl-1) combination; the callus differentiated Protocorm-like bodies (PLBs). After subculturing, calli initially exhibited 3 different appearances: light green, yellow, and light brown. The light green calli grew rapidly, consisting compact mass of isodiametric granules, and produced 1.2 PLBs on an average per 0.5 cm diameter of callus on MS medium without growth regulators. Subsequently, the PLBs were inoculated on 4 different nutrient media such as MS, Gamborg B5, Vacin and Went, and M for the differentiation of shoots and roots. After 6 wks, about 4.2 plantlets were formed from each PLB on MS basal medium; the highest shoot length (7.4 cm) and a greater number of leaves (3.8) on average were observed in the plantlets in this combination. The regenerated plantlets displayed maximum survival frequency (100%) in the potting medium with the combination of charcoal and brick pieces. The method can be successfully used for mass propagation of the species.
Tropidia curculigoides Lindl. a rare terrestrial orchid is reported for the first time from Chilkigarh forest of Jhargram district, West Bengal, India. The present communication provides its taxonomic description, morphology of pollinium under SEM, habitat ecology, and distribution.
Orchids are one of the immense ecological and evolutionary momentous plants and have effectively colonized almost every habitat on the earth. The seeds of Pholidota imbricata W. J. Hook. were aseptically grown on four nutrient media namely KC, MS, PM, MVW and these successfully germinated on all of the tested media. The highest percentage of seed germination (80.00%) was achieved on MS medium and greenish protocorms were obtained. During phytochemical screening, secondary metabolites i.e. alkaloids and ten other compounds namely, steroids, flavonoids, glycosides, phlobatannins, terpenoids, quinine, coumarin, anthroquinones, saponins, and tannin were recorded in both natural and in vitro developed plant parts. The comparative results of the alkaloid test revealed that in vitro developed plant parts showed better results than those of naturally grown ones. Comparative results of ten secondary metabolites tested in naturally grown plant parts were better than in vitro grown plantlets. The current investigation provides new inventions on the competency of P. imbricata and enhances the continued inquiry of medicinal orchids, in Bangladesh.
Sarat Misra. 2022. Similipal: The Forest of Hundred Orchids. Wildlife organization, Forest and Environment Department, Government of Odisha, Bhubaneswar, India. Pp. 360. Sarat Misra is a founder member of The Orchid Society of India and also served as its Councillor. He is an expert in exploring the Indian orchids. He is a member of State Board for Wildlife and Odisha Environmental Society, and IUCN Species Survival Commission in the Orchid Specialist Group. This book Similipal: The Forest of Hundred Orchids deals with the morphology and lifeform of the orchids of Similipal forest of Odisha that has the credit of a National Park, a Tiger Reserve, and a Biosphere Reserve. This book with elaborate information on all aspects of orchids will be very useful to Foresters, Plant Scientists, Research Scholars, and to the Hobbyist interested in study of orchids, not only for Similipal but also for other regions of India.