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In the present study, an in vitro regeneration protocol for Glossonema varians (Stocks) Benth. ex Hook.f. of family Asclepiadaceae was optimized. Cotyledonary nodes of in vitro cultured seedlings were used as explants for activation of axillary shoot buds. Axillary shoot buds were initially activated on 0.1 mg L−1 6-benzylaminopurine (BAP) and then multiplied on 0.05 mg L−1 BAP. Shoots were rooted in vitro on 1/4 strength Murashige and Skoog medium containing 0.1 mg L−1 2-naphthoxyacetic acid and 100 mg L−1 activated charcoal. The cultures were maintained in a 12 h photoperiod at 40-50 μmol m−2 s−1 spectral flux photon, 25-30 ± 2°C, and 60% relative humidity (RH). Up to 80% of in vitro regenerated plantlets were acclimatized on soilrite in cotton-plugged culture tubes in the greenhouse. This protocol can be a useful method to mass propagate and conserve this rare plant to balance biodiversity in the desert ecosystem. [ABSTRACT FROM AUTHOR]

Tissue culture methods for plant regeneration have been developed for Lasiurus scindicus, Sorghum halepense and Urochloa panicoides using basal portion of young inflorescence as new and a potential source(s) of explants. Highly embryogenic cultures were initiated on Murashige and Skoog's (MS) medium supplemented with various concentrations of 2,4-dichlorophenoxyacetic acid (2-4,D). The regenerative cultures were maintained by subculture on MS medium in the dark at 26±2°C. Plants were regenerated via somatic embryogenesis from the competent cell cultures on hormone-free MS basal medium or MS medium with 1 mgl-1 kinetin. Somatic seedlings were successfully transplanted to pots and grown to maturity in field. Polyamine levels were analyzed in embryogenic and non-embryogenic cultures. A correlation has been found between the individual polyamine levels and the ratio of putrescine to spermidine in the cultured tissues with plant regeneration ability via somatic embryogenesis. [ABSTRACT FROM AUTHOR]

The article presents the discussion on Indian Thar Desert being a home to endemic, rare and threatened plant species of all growth forms. Topics include enumerated geographic distribution pattern, threat status, and conservation for some species and suggested use of modern tools such as ecological niche modelling for population; and colourful pattern of larvae and presence of number of tentacle pairs.

Mitragyna parvifolia (Roxb.) Korth., commonly known as "Kadam," is an endangered and pharmaceutically valued tree of the family Rubiaceae. The numerous medicinal properties are attributed to the various alkaloids of this plant. Poor seedling survival (due to very small size of seeds, approximately 10,000 per gm), overexploitation and habitat destruction are the major constraints in conserving the wild stocks of this species. This paper reports a significant, improved, and repeatable micropropagation protocol of M. parvifolia using nodal explants of a mature tree. Nodal explants harvested during spring season from the lopped tree differentiated the maximum number of axillary shoots (5.3 ± 0.82 per node) on full-strength Murashige and Skoog (MS) medium containing 3.0 mg L−1 6-benzylaminopurine (BAP) and additives (25 mg L−1 each of adenine sulfate, L-arginine, and citric acid and 50 mg L−1 ascorbic acid). Shoots were amplified in vitro through (1) recurrent transfer of mother explants and (2) subculturing on fresh nutrient medium. The greatest number of shoots (13.4 ± 1.26) with an average length of 6.2 ± 1.03 cm was produced after 4 wk on MS medium containing 0.5 mg L−1 BAP, 0.25 mg L−1 kinetin (Kin), 0.1 mg L−1 Indole-3-acetic acid (IAA), additives, 100 mg L−1 activated charcoal (AC), and 0.8% (w/v) agar. This is the first report of concurrent ex vitro rooting and acclimatization (CEVRA) in M. parvifolia. About 90% micropropagated shoots rooted ex vitro on pulse treatment of 500 mg L−1 Indole-3-butyric acid (IBA; for 5 min) and produced 8.5 ± 0.97 roots per shoot with an average length of 9.40 ± 1.06 cm, after 5 wk. Over 80% of CEVRA plantlets were successfully transplanted to the soil in field. The defined protocol can be employed for conservation ex situ and restoration/rehabilitation/reintroduction in situ of M. parvifolia. [ABSTRACT FROM AUTHOR]

Mollugo nudicaulis Lam., commonly known as John’s folly or naked-stem carpetweed, is an ephemeral species of tropical regions. The plant is ideal to study the eco-physiological adaptations of C3-C4 intermediate plants. In the present report, in vitro growth profiling of the plant and comparative leaf anatomy under in vitro and ex vitro conditions were studied. In vitro propagation of the plant was carried out on Murashige and Skoog (MS) basal medium augmented with additives and solidified with 0.8% (w/v) agar-agar or 0.16% (w/v) Phytagel™. The concentration of plant growth regulators (PGRs) in the basal medium was optimized for callus induction, callus proliferation, shoot regeneration, and in vitro rooting. The optimum callus induction was obtained from M. nudicaulis seedling hypocotyls. The highest regeneration induction of about 88% or nearly 41 shoots with about 142 leaves per culture vessel was observed from friable callus on MS basal medium solidified with Phytagel™ and containing 4.44 μM 6-benzylaminopurine, 4.65 μM kinetin, 2.69 μM naphthaleneacetic acid, and 0.91 μM thidiazuron. In leaf anatomy, differences related to photosynthetic tissue organization were observed in leaves of in vitro and ex vitro plants, which indicated that changes in the environment affected the anatomy of subsequent leaves in plants. This is the first report of an efficient micropropagation protocol for M. nudicaulis, using an indirect organogenesis method. Efforts were made to optimize the concentrations of various PGRs and organic compounds for in vitro growth of regenerated shoots. [ABSTRACT FROM AUTHOR]

Flavonoids in Calligonum polygonoides Linnaeus extract were separated, detected, and identified by reverse-phase high-performance liquid chromatography (RP-HPLC) with electrochemical detection (EC) in combined isocratic and gradient elution using a glassy carbon or a boron doped diamond electrode. Ultrasonication coupled with a microwave-assisted technique was developed to optimize the extraction of the phenolic compounds. The total antioxidant capacity was quantified using the DPPH. method and voltammetry. The RP-HPLC-EC led to the detection of nine different flavonoids: catechin, delphinidin, fisetin, myricetin, epicatechin, kuromanin, rutin, callistephin and procyanidin A2, in a single run by direct injection of the sample extract solution. [ABSTRACT FROM AUTHOR]

Abstract: Leptadenia reticulata (Retz.) Wight. & Arn. is an important medicinal plant, belongs to the family Asclepiadaceae. This plant is known for its medicinal uses since 4500 BC. Presently this is an endangered species (Arya et al., 2003). Six shoots (2–4cm long) per node differentiated on MS medium+5.0mg/l of BAP+additives. Incorporation of additives in the culture medium promoted growth of cultures. The shoots differentiated per explant were repeatedly transferred on to fresh MS+1.0mg/l of BAP+0.1mg/l of NAA and additives. The regenerated shoots were subcultured for further multiplication on MS+1.0mg/l BAP+0.5mg/l Kin+2-iP (0.5mg/l) and 0.1mg/l of NAA+additives regularly after an interval of 3 weeks. Addition of ammonium sulphate in the medium resulted in increase in shoot number and promoted elongation also growth of cultures was sustained even if subculturing was delayed (26±2 days). Success was also achieved in defining protocol for in vitro regeneration of shoots from petiole derived callus. Shoots regenerated in vitro by both processes were rooted in vitro on 1/4 strength of MS medium+3.0mg/l of IBA after 15–20 days. Cent percent of the shoots rooted ex vitro, if the in vitro regenerated shoots were treated with 200mg/l of IBA. The in vitro–ex vitro rooted plantlets were hardened under different regimes of temperature and humidity in a greenhouse. The hardened plantlets were transferred to soil in polybags. More than 95% plants survived in field conditions. Total dry biomass harvested per year was 2800kg/acre. [Copyright &y& Elsevier]

Blyttia spiralis (Forssk.) D.V.Field & J.R.I.Wood, a threatened and medicinally important plant, belongs to the family Apocynaceae. Widespread habitat destruction has adversely affected natural populations of this species. This paper reports the first efficient plant propagation system for B. spiralis using nodal segments as explants. The greatest number of shoots was obtained on Murashige and Skoog (MS) medium containing 6-benzylaminopurine (BAP; 4.0 mg L) through bud breaking. Shoots were further multiplied through repetitive transfer of original explants and by subculturing of in vitro-raised shoots. Key physiochemical factors affecting various stages of micropropagation were systematically tested. The maximum number of shoots (35.45 ± 2.64), with a mean length of 6.69 ± 1.03 cm, was achieved on 0.8% agar-gelled shoot proliferation medium (SPM: MS + 0.5 mg L each of BAP and kinetin [Kin] + 0.1 mg L α-naphthaleneacetic acid [NAA]), with a combination of 50 mg L ascorbic acid; 25 mg L each of citric acid, l-arginine, and adenine sulfate; and 150 mg L ammonium sulfate and 100 mg L activated charcoal (AC) in culture bottles. In tests of rooting conditions, 61.5% of the shoots rooted in vitro on ¼-strength MS medium containing 2.0 mg L indole-3-butyric acid (IBA) and 200 mg L AC; 89.4% of the shoots rooted ex vitro in Soilrite®, if the shoot bases were pretreated with 250 mg L IBA for 5 min. Plantlets rooted by both procedures were gradually acclimatized in a greenhouse. About 85% of ex vitro-rooted and 55% of in vitro-rooted plantlets were successfully established in soil. The described method can be employed for the large-scale propagation and conservation of Blyttia spiralis. [ABSTRACT FROM AUTHOR]

Abstract: To ascertain the conservation priorities and strategies for Commiphora wightii, an endangered medicinal plant of Indian Thar Desert, genetic diversity was estimated within and among different populations. The total of 155 amplification products were scored using ten each of RAPD and ISSR primers, exhibiting an overall 86.72% polymorphism across 45 individuals representing eight populations. The cumulative data of two markers were used to compute pair-wise distances. The Neighbor-Joining tree revealed high genetic differentiation among populations except Kiradu population. Nei's gene diversity (h) ranged between 0.082 and 0.193 with total diversity at species level is 0.294. Shannon's information index (I) ranged between 0.118 and 0.275 with an overall diversity of 0.439. Analysis of molecular variance showed more diversity among population level (56.65%) than at within population level (43.35%). The low gene flow value (Nm=0.349) and high coefficient of genetic differentiation (GST =0.589) and high fixation index (FST =0.566) demonstrated elevated genetic differentiation among the population and can be predicted that these populations are not in Hardy–Weinberg proportions. Principal Co-ordinate Analysis confirms that Akal population has become phylogenetically more distinct and less diverse than the rest of the samples. Mantel's test revealed no correlation between genetic and geographical distances of populations (R2 =0.122). Overall highest diversity was observed in the population of Machiya Safari Park and Kiradu, while lowest in Akal population, later may constitute an evolutionary significant unit, having merit for special management. [Copyright &y& Elsevier]

Aims: To survey the occurrence of nodulated legumes in the arid and semi-arid areas of Western Rajasthan and to characterize their associated symbiotic bacteria. Methods: Herbaceous annual species were excavated whole, while tree species were studied as seedlings in the field or as trap plants in pot experiments. Nodules were examined by microscopy to confirm their effectiveness and to determine their internal structure. Bacteria isolated from the nodules were authenticated on their original hosts and were identified on the basis of 16S rRNA sequencing. Phylogenetic trees were inferred using the neighbour-joining method. Results: We studied 35 of more than 50 species of native legume reported from these areas. Legumes are drought escaping (annual species), drought tolerant perennials or trees possessing deep root systems and other adaptations to arid conditions. Nodulation was recorded in all members of the Papilionoideae and Mimosoideae, but only one species of Caesalpinioideae. Internal structure of nodules varied within these groups, especially with respect to the presence or absence of uninfected cells in the infected region. Full 16S rRNA gene sequencing revealed that the nodules harboured a range of nodulating bacteria belonging to the genera Sinorhizobium, Rhizobium and Bradyrhizobium, within which they formed separate sub clades. Conclusions: This study extends the range of legumes known to grow and nodulate in semi-arid regions, and provides information about their endosymbionts. [ABSTRACT FROM AUTHOR]

Abstract: Isolation of intact and pure genomic DNA (gDNA) is essential for many molecular biology applications. It is difficult to isolate pure DNA from mature trees of hot and dry desert regions because of the accumulation of high level of polysaccharides, phenolic compounds, tannins etc. We hereby report the standardized protocol for the isolation and purification of gDNA from seven ecologically and medically important tree species of Combretaceae viz. Anogeissus (Anogeissus sericea var. nummularia, Anogeissus pendula, and Anogeissus latifolia) and Terminalia (Terminalia arjuna, Terminalia bellirica, Terminalia catappa and Terminalia chebula). This method involves (i) washing the sample twice with Triton buffer (2%) then (ii) isolation of gDNA by modified-CTAB (cetyl trimethyl ammonium bromide) method employing a high concentration (4%) of PVP (Polyvinylpyrrolidone) and 50mM ascorbic acid, and (iii) purification of this CTAB-isolated gDNA by spin-column. gDNA isolated by modified CTAB or spin-column alone were not found suitable for PCR amplification. The Triton washing step is also critical. The quality of DNA was determined by the A 260/A 280 absorbance ratio. gDNA was also observed for its intactness by running on 0.8% agarose gel. The suitability of extracted DNA for PCR was tested by amplification with RAPD primers, which was successful. Further, rbcLa (barcoding gene) was amplified and sequenced to check the quality of extracted gDNA for its downstream applications. [Copyright &y& Elsevier]