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An elite cultivar of W. somnifera - WSR with desired attributes exhibiting uniform chemical profile and better adaptability in varied environment has been developed by Indian Institute of Integrative Medicine (IIIM), Jammu. The cultivar is consistently hyper-productive in root/leaf biomass and phytochemical attributes and received commercial acceptability in India. A highly efficient in vitro micropropagation system has been developed for this elite cultivar for mass propagation. Field performance, LC-MS based Withanolide profile and Randomly Amplified Polymorphic DNA (RAPD) marker based analysis of micropropagated plants confirmed clonal fidelity of tissue culture raised plants. Adoption of presently developed in vitro strategy for propagation of cultivar WSR would help to provide uniform planting material which is highly desirable from pharmacological point of view to maintain uniformity and efficacy of herbal drug preparations utilizing Indian Ginseng.

If left unpollinated, the flowers ofAerides multiflora (Roxb.) andRhynchostylis retusa (L.) Bl. can remain fresh for 17 and 24 d, respectively. However, they begin to wilt at 2 to 3 days after pollination (DAP) and 3 to 4 DAP, respectively, and become senescent at 5 DAP and 7 DAP, respectively. When measured at two developmental phases — Stage 1, start of wilting and Stage 2, progression to senescence — all the floral organs from pollinated flowers had higher contents of total soluble sugars, reducing sugars, and free amino acids than those from unpollinated flowers. A corresponding increase was noted in the activities of hydrolytic enzymes, i.e., α-amylase, β-amylase, and invertase, and proteolytic enzymes (proteases) in those organs. This indicated that signals related to pollination had up-regulated those activities, leading to a breakdown of complex molecules into simpler ones for mobilization. The amounts of sugars and enzyme activity were relatively greater in the pollinated flowers ofA. multiflora compared withR. retusa, and levels were always higher in the floral lips and perianths. When inhibitors of auxin (0.25 mM TIBA) or ethylene (0.25 mM AgNO2) were applied to the pollinated flowers, their senescence was partially prevented, thus signifying hormonal involvement in governing the pollination-induced biochemical alterations normally found in those organs.

Withanolides-steroidal lactones, isolated from various Solanaceous plants have received considerable attention due to their potential biological activities. Five selected withanolides (withanone, withaferin A, withanolide A, withanolide B, withanolide E) were identified by HPLC-UV (DAD) — positive ion electrospray ionization mass spectroscopy in Withania somnifera (L.) Dunal cv. WSR plants and tissues cultured in vitro at different developmental phases. Cultures were established from five explants on Murashige and Skoog’s medium supplemented with different plant growth regulators. Results suggest that production of withanolides is closely associated with morphological differentiation.

Field explorations in Himachal Pradesh (2002-2010) have resulted in documenting some new distributional records of orchids for the state. They exhibited a variety of life forms (epiphytes/ terrestrials/ lithophytes) and are mostly distributed in the temperate hills. Present communication provides notes on taxonomy, distribution, habitat ecology and conservation of Neottia listeroides Lindl., an interesting leafless orchid in the state.

Bulbophyllum dickasonii Seidenf. is reported for the first time from Manipur as an addition to the orchid flora of India. Morphological features of leaves and anther cap which are lacking in the original description are described, and colour photographs are provided.

Bambusa tulda and Thyrsostachys siamensis resemble each other in having an obovate ovary which is hairy and thickened along the apex, a pseudo-crassinucellate ovule with a wide region of attachment, poorly-developed and ephemeral outer integument, an inner integument which fails to grow beyond the nucellus, «Polygonum» type of embryo sac ontogeny, parallel orientation of embryo sac to the long axis of the ovule, multiple antipodals which retain apical position in the embryo sac even during post-fertilization phase of development, an ephemeral nucellus, relatively small «bambusoid» embryos, and many-layered and apically thickened pericarp. However, they differ from each other in their gynoecial structure, the extent of the development of the outer integument, organization of megaspore tetrads and development-stage-related behaviour of the inner integument in the fertilized ovules. These taxa also differ from other members of the subfamily Bambusoideae in the structure of the mature ovule, endosperm and pericarp.

The orchids are highly diverse, habitat specific and actively evolving plants, known for their beautiful and long-lasting flowers. They are amenable to variety improvement and have added significantly to the growth of international trade in cut flowers and potted plants. The orchids are cultivated as a cash crop in several countries. Many orchids are valuable herbs, used to cure a variety of fertility and virility related problems; their importance in treating nervous, cardiac, rheumatic, dermal, respiratory, and digestive disorders is also well documented. In India, the orchids are represented by over 1,300 species, but their commercial cultivation is still in its infancy due mainly to non-availability of proper planting material and cultivation procedures. Progressive loss of orchid diversity due to unregulated collection and habitat destruction pressures has been an added constraint. This paper briefly discusses some possibilities for sustainable development (conservation, propagation, value addition) of Indian orchids for community benefit, using both the conventional and molecular techniques.

In vitro asymbiotic seed germination potential of its immature seeds (36 weeks after pollination) of G. calceolaris was successfully tested on three different agar gelled nutrient media i.e. Murashige and Skoog (MS), Mitra et al. (M) and potato dextrose agar (PDA). Seeds germinated within 15.75+/-0.75 to 35.75+/-0.75 days in the three different media. The protocorms developed therefrom subsequently differentiated into first leaf and root primordia, and complete seedlings were obtained within 111.25+/-1.25 to 141.25+/-1.25 days on MS and M media. The protocorms, though failed to differentiate further on basal PDA medium, despite repeated subculturings, incorporation of peptone (P; 1 gl(-1)), yeast extract (YE; 2 gl(-1)) and coconut water (CW; 20%) in the medium proved beneficial in inducing differentiation, in these germinating entities. Additional use of growth additives (P/YE/CW), in general, favoured better germination, protocorm formation and seedling development. The optimal nutritional combination during seed germination, protocorm growth and multiplication and seedling development was found to be CW (10%) enriched MS medium.

The orchids are invariably mycorrhizic; they require a fungal stimulus for seed germination in nature and harbour an endotrophic and intracellular fungus in one or more of their organs. In the adult plants, the fungal infections are almost always pathogenic initially and lead to the development of several rejection reactions in the host cells like resistance to fungal entry, hypertrophy of cells and nuclei, and production of fungistatic compounds — phytoalexins. The phytoalexins keep the further growth of fungus under check in the deeper tissues so as to maintain a certain balance between the endophyte and the host cells. After gaining entry into the cortical zone, the fungus develops characteristic pelotons and the host cells, in response, secrete certain hydrolytic enzymes to breakdown and digest the hyphae as a measure of aggressive mode of host cells towards their endophytic fungus. Since after digestion of fungal hyphae, the host cell appears to utilize the nutrients brought by the fungus and other metabolites produced as a result of fungus degradation, the orchid seems to have become parasitic on fungus. This process of continued infection and digestion continues for the full length of orchid life suggesting thereby that orchid and fungi are now in a mutual beneficial association. Each satisfies the need of other; the fungus secretes certain vitamins such as niacin, thiamine, nicotinic acid etc. into the host cells, whereas orchid seed satisfies the vitamin requirement of the fungus by releasing para-aminobenzoic acid, a constituent of folic acid.

The orchids represent a group of botanically interesting and commercially significant plants which have outnumbered and outsmarted their counterparts by evolving ingenuity and higher levels of specializations. They comprise nearly 20,000 species in 800 genera, culminate one of the evolutionary lines of monocots, and are still in an active state of speciation due to poorly developed barriers of reproductive isolation. Suppressed development of endosperm, microscopic seeds with undifferentiated embryos, and dependence upon a variety of factors including specific pollinators and fungi for continued reproduction in nature are some of their distinguishing features. The orchids possess extremely beautiful, intricately fabricated, highly colourful, and long-lasting flowers of myriad sizes and have significantly contributed to the development of international trade in cut-flowers and pot-plants. Possibilities of producing new and novel varieties through successful wide matings have added new dimensions to the significance of these plants in the trade; they rank among the top ten sought after plants for cut-flower production. Many of them are rich in phytochemical contents as well and are extensively used in local medicines for their curative and aphrodisiac properties. Thailand, Singapore, Malaysia, Taiwan, Korea, and Sri Lanka are the major asian players in the orchid trade with Japan and U.S.A. as the biggest export destinations.

This study was carried out to evaluate the differential responses of 6-benzyladenine (BA) and α-naphthaleneacetic acid (NAA) on regeneration competence of pseudobulb segments of Dendrobium moschatum Sw., an epiphytic orchid of immense ornamental importance. Mitra et al. (1976) media supplemented with different (0.5–2 mgl−1) concentrations of BA and NAA were employed to elucidate their multivariate effects on morphogenetic parameters using response surface methodology. Surface analysis clearly indicated that regeneration response, at both lower and higher concentrations of BA, increased with increase in NAA levels. The proliferative potential of pseudobulb explants was markedly influenced by their position on donor axis; basal segments were better used for inducing multiple proliferative loci. An average of 28.8 plantlets could be harvested on medium supplemented with BA (2mgl−1) and NAA (0.5mgl−1) within 24 weeks. The present protocol can serve as an aid for propagation and conservation of diminishing natural populations of D. moschatu.

A survey of orchids from various Indian provinces identified a variety of different species, including Cymbidium aloifolium , Cymbidium Hybrid (Arabian Sea), C. ividioides , Epidendrum sp., Liparis botanensis , Phaius tankervilleae and Pholidota imbricate , which showed virus-like symptoms including flower colour break, leaf necrosis and necrotic spotting. These symptoms were similar to those reported earlier for Cymbidium mosaic virus (CymMV) (Zettler et al ., 1990). Sap from these plants was inoculated onto Datura stramonium and Chenopodium murale , inducing blotchy local lesions which varied with plant species, season and environmental conditions. CymMV was detected in these indicator plants and the orchids with symptoms using a polyclonal DAS-ELISA kit (Agdia Inc., Elkhard, IN, USA). When examined by transmission electron microscopy, partially purified virus preparations showed the presence of 440–480 nm flexuous particles, which showed enhanced trapping and clumping with CymMV antiserum (obtained from Dr Z. Maat, the Netherlands) in immuno-electron microscopy. RT–PCR was performed using the primer pair UI and LI (Seoh et al ., 1998) and a product of expected size ( ∼ 534 bp) was amplified. This product was cloned and sequenced and was found to share 94% sequence homology with the 5 ′ end of the RdRp gene of Korean type 2 isolate of CymMV (accession no. AF016914). This is the first definitive report of CymMV infecting orchids in India.

Cytological investigations were carried out in 18 species belonging to 13 genera. Teucrium quadrifarium (n=15) represents the first chromosome count for the species. New cytological types were observed in Ocimum canum (n=32+0-4B), O. sanctum (n=16+0-3B), Perilla ocimoides (n=14+0-2B) and in Calamintha clinopodium (n=20). For the remaining taxa, one or all the earlier chromosome reports were confirmed. Meiosis was normal in most of the taxa. The discordant chromosome numbers known in the family make it difficult to consider it as monobasic. Ocimum canum (8x) and Pogostemon plectranthoides (8x) represent the highest grade of ploidy. Intra-specific polyploidy is evident in Ocimum sanctum (2n=32, 64), O. canum (2n=24, 64, 128) and Ajuga macrosperma (2n=16, 32). Aneuploidy is equally common in the family at both the generic and specific levels.

Young leaf segments from plants growing both in vivo and in vitro were cultured on Mitra et al medium (BM) supplemented variously with auxins (IAA, NAA, 2,4-D), kinetin (KN), GA3, and organic supplements (peptone, urea, casein hydrolysate, and yeast extract). The explants from mature leaves did not show any growth and turned necrotic, while those obtained from juvenile leaves of 6-mo-old plantlets growing in vitro developed protocorm-like bodies (plbs) at their cut surfaces within 4-7 wk, depending on the growth medium. Histological studies revealed their epidermal origin. Formation of plbs subsequently spread all along the explant and suggests a meristematic/generative potential of the epidermal cells in immature leaves. Upon subculture in basal medium, the plbs differentiated into plantlets within 4-5 wk. Although regeneration of plbs was achieved in BM and the auxins or GA3, KN in combination with IAA/NAA in the presence of peptone accelerated their formation.

Cytological studies were made in Cenchrus biflorus (n=16, 17, 18), C. ciliaris (n=18, 18+0-2B's) and C. setigerus (n=17). Different cytotypes in the first two species overlapped in their morphological traits. Predominant occurrence of the cytotypes n=17 (C. biflorus) and n=18 (C. ciliaris) suggests their stability in the area under study. A heavy natural selection on the other hand explains the rarity of new chromosome types n=16, 18 in the former and n=18+0-2B's in the later species respectively.Dibasic nature of Cenchrus with x=9 and 17 is evident and majority of its speciation seems to have centered around the later number. Complete bivalentization and 18 duplets point to an amphiploid nature of C. biflorus, whereas, variable number of bivalents and/or quadrivalents together with the categorization of somatic chromosomes as 9 quadruplets (C. ciliaris) and 8 quadruplets and one pair (C. setigerus) indicates chromosomal homologies.

Cytological studies were carried out in 14 N. Indian taxa. Centranthera hispida (n=15) and Verbascum celsioides (n=18) represent the first chromosome counts for the genus and the species respectively. Two cytomorphotypes with n=7 and n=14 in Vandellia crustacea were also unknown earlier. For the remaining taxa one or the other earlier chromosome reports are confirmed. Meiosis was normal in most of the taxa. Secondary associations were observed in Verbascum thapsus and V. celsioides. Multiple associations in Antirrhinum majus (2x) represents interchange heterozygosity. Intraspecific aneuploidy in Verbascum thapsus (2n=34, 36), Antirrhinum orontium (2n=14, 16), intraspecific polyploidy in Antirrhinum majus (2n=16, 32), Veronica anagallis (2n=18, 36, 54) and both polyploidy and aneuploidy are evident in Vandellia crustacea (2n=14, 28, 32, 42). Origin and evolution of the tetraploid taxon in the last species is discussed.

Thirty-one species and varieties of 8 North-Indian Convolvulaceous genera were investigated. Normal diploid like meiotic behaviour was evident in most of these. Polyploid nature of Ipomoea batatas and some desynaptic bivalents in Merremia aegyptia accounted for aberrant meiosis. Some desynaptic bivalents were also observed in I. bonanox, Porana paniculata and Calystegia hederacea.Ipomoea chryseoides (n=15), I. mutabilis (n=15+O-1B), I. dichroa (n=15), I. palmata (white flowered type n=15+1B) and Argyreia campanulata (n=14) represent first chromosome counts for these species. Lowest and highest chromosome numbers n=9 and n=45 were encountered in Jacquemontia pentantha and Ipomoea batatas respectively.Poor incidence of polyploidy may either be due to a meagre cytological coverage or the secondary nature of the high basic numbers met in the family. Aneuploidal relationship of the different species/genera is evident. Importance of aneuploidy and polyploidy in the evolution of Convolvulaceae is discussed.Morphological variability in Ipomoea aquatica, I. eriocarpa, I. fistulosa, I. palmata and I. pestigridis seems to be correlated with the cytological features.

Sixteen taxa belonging to ten species of Aloe were investigated. Most of these species exist only as diploids. A. arborescens was found to be tetraploid, whereas, both diploid and tetraploid individuals were studied in A. arborescens var. natalensis, A. latifolia and A. vera. Apart from unreduced gametes and hybridization, the origin of polyploidy in the genus is attributed to mitotic system as well.Split metaphases/anaphases and/or non-orientation and ultimate exclusion of some of the chromosomes accounts for aneusomatic cells (2n=9, 10, 11, 12) in A. aristata. Non-disjunction leading to unequal anaphases explains such cells in A. humilis (2n=13, 15) and A. vera (2n=15). Somatic pairing as observed in A. ferox may also result in such unequal segregations. While, the aneusomatic cells were observed in the gametic tissue as well in A. vera, their absence in the meiotic tissue in A. aristata and A. humilis indicates that these cells are not selected in the germ line.Different species presently studied, though exhibited a gross similarity in the morphology of their bimodal karyotype, differed from one another in their total chromatin length, F% and S% ratios. Satellites were observed on the long arm of large chromosomes in A. arborescens var. natalensis, A. ferox and A. vera. In A. saponaria only one chromosome of a long pair possessed satellite.Hybrid nature of the polyploid taxa in A. latifolia and A. vera is apparent, on the basis of their karyotypes. In A. arborescens, polyploidy explains meiotic abnormalities, whereas, structural heterozygosity accounts for such aberrations in A. africana, A. ferox, A. transvaalensis and A. vera (2x).

Two species of Cypripedium and four of Paphiopedilum have been cytologically investigated. Polysomaty and aneusomaty has been noticed in C. cordigerum, a diploid species, in the root-tip squashes. ...

Cytological observations in 26 taxa belonging to 21 species of Orchideae (Orchidaceae) from the Eastern Himalayas are presented. Twelve taxa were investigated for the first time. Intraspecific poly...

SUMMARYCytological observations on 18 taxa belonging to 9 genera of Neottieae (Orchidaceae) from the Eastern Himalayas are presented. Three species are investigated for the first time. Intraspecific polyploid complexes are discovered in Zeuxine strateumatica. Intraspecific aneuploidy is noticed in Spiranthes sinensis, and seems to occur also in Cephalanthera ensifolia and Epipactis latifolia in the Himalayas. The taxonomic status of the cytological races is discussed.