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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]

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]

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]

Momordica dioica Roxb. ex Willd., is a perennial and dioecious (2n = 28) plant of family Cucurbitaceae. Conventional methods of propagation through seeds, stem cuttings and rhizomatous/tuberous roots are inadequate for its mass cultivation as a vegetable crop. This paper reports an improved and efficient micropropagation method for wild female M. dioica using nodal explants. Shoot amplification was achieved using subculturing of in vitro raised shoots on MS medium supplemented with various concentrations of 6-benzylaminopurine (BAP) alone or in combination with indole-3-acetic acid (IAA). The maximum number of shoots (45.30 ± 3.83) with an average length 6.52 ± 0.89 cm were differentiated on MS medium containing 0.5 mg L BAP, 0.1 mg L IAA and additives (50 mg L ascorbic acid, 25 mg L each of adenine sulphate, citric acid and l-arginine). The cloned shoots were rooted ex vitro. Each shoot treated with 250 mg L IBA for 5 min produced 12.3 ± 1.33 with a mean length 5.4 ± 0.73 cm. More than 85% (46 plants) of ex vitro rooted plantlets were successfully hardened in a greenhouse with normal growth characteristics. In order to evaluate the genetic stability of micropropagated plants, the two PCR-based techniques, Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeats (ISSR) were used. The amplification patterns of the micropropagated and mother plant were monomorphic thus depicting genetic stability of the micropropagation system. This protocol could be effectively employed for the mass multiplication of wild female M. dioica, a popular summer vegetable crop. [ABSTRACT FROM AUTHOR]

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]

An efficient regeneration protocol for Sarcostemma acidum - an important medicinal plant has been established. Callus initiated from nodal explant on MS medium with 2.0 mg L of NAA + additives. Callus initiated was subcultured on MS medium containing various concentrations of NAA or 2,4-D. Out of these combinations, MS medium +1.0 mg L of NAA + additives was found to be effective for the multiplication of callus. Subculture was done after an interval of 20-22 days. For differentiation of callus BAP or Kinetin alone was found to be less effective. Maximum frequency of shoot regeneration recorded on MS medium +1.0 mg L of BAP + 0.5 mg L of Kinetin and 0.1 mg L of NAA + additives. The in vitro differentiated shoots were excised and inoculated on 1/4 strength MS medium +2.0 mg L of IBA + 0.02 % activated charcoal for in vitro rooting. Maximum response (90 %) was recorded on this medium. In vitro differentiated shoots were inoculated on autoclaved soilrite® after treatment with root inducing auxins. Ex vitro rooting in this plant species has been reported for the first time. Eighty five percent of the shoots rooted under ex vitro conditions. Both in vitro and ex vitro rooted plantlets were hardened in a green house. [ABSTRACT FROM AUTHOR]

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]

n in vitro propagation method for female plants of Momordica dioica (Roxb.) has been established. The nodal segments were harvested and the cut ends of the explants were sealed with wax and then surface sterilized and cultured. Bud breaking occurred on Murashige and Skoog's (MS) agar-gelled medium + 2.0 mg L 6-Benzylaminopurine (BAP) + 0.1 mg L Indole-3 acetic acid (IAA). The cultures were amplified by passages on MS medium supplemented with 1.0 mg L BAP + 0.1 mg L IAA. Further, shoot amplification (29.2 shoots per vessel) was achieved by subculturing of in vitro regenerated shoot clump on MS medium + 0.5 mg L BAP + 0.1 mg L IAA. The micropropagated shoots were subsequently transferred for root formation on half-strength MS medium + 2.0 mg L Indole-3 butyric acid (IBA) with 89% success rate. The in vitro-regenerated shoots were also rooted ex vitro with 34% success. These plantlets were hardened in the greenhouse and transferred to the field. The established protocol is suitable for true to type cloning of mature female plant of M. dioica. [ABSTRACT FROM AUTHOR]