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Zizyphus mauritiana is a medicinally important plant species of arid ecosystem. High degree of heterozygosity, over exploitation and low multiplication rate are major constraints in propagation of this plant species. Here we report a cost-effective cloning protocol of Z. mauritiana. Murashige and Skoog (1962) medium with BAP (2.0 mg 1-1) + additives found suitable for axillary shoot induction from mature nodal explant. On this medium 2.8 ± 0.67 shoot were produced from each axillary meristem. Shoots were further multiplied by sub-culturing in MMS medium containing various concentrations of plant growth regulators (BAP, Kn, 2iP) in different combinations. The in vitro propagated shoots were treated with IBA or/and NOA for ex vitro rhizogenesis. Ex vitro rooted plantlets were transplanted to the soil with 95% rate of survival. These plantlets were tested for genetic homogeneity using SCOT marker. For the tested primers, non-detectable variation was observed in DNA profiling among the micropropagated plants and the mother plant. To the best of our knowledge, this is the first report on concurrent ex vitro rhizogenesis with acclimatization and SCOT based genetic homogeneity assessment of Z. mauritiana. Optimal multiplication and higher survival rate coupled with clonal stability, ensures the effectiveness of the protocol. [ABSTRACT FROM AUTHOR]

Abstract: An in vitro propagation and tuberization method was successfully established for Eulophia nuda Lindl., an endangered orchid of Aravalli hills. Shoot buds were induced from tuber explants (1cm cut pieces) on Murashige and Skoog (MS) medium containing 44.4μM 6-benzyladenine (BA) and additives (283.8μM ascorbic acid, 67.8μM adenine sulphate, 143.5μM arginine and 118.9μM citric acid). After excision of newly formed shoots, explants were successively transferred to MS medium with 22.2μM BA and additives for shoot multiplication up to three passages. Further shoot multiplication and tuberization was achieved, by subculturing of in vitro-formed shoots, on MS medium containing 8.88μM BA, 4.68μM Kinetin (Kn) and additives. Shoot multiplication was influenced by cytokinin type, concentration and combinations. Shoots with tubers were successfully rooted in vitro and ex vitro. Shoots were treated with 2.46mM indole-3-butyric acid (IBA) for 4min for ex vitro rooting. Plantlets were acclimatized in the greenhouse conditions in bottles containing soilrite. Acclimatized plantlets were transferred to the earthen pots containing soil as a mixture of clay, sand and vermicompost (1:1:1). In vitro tuber formation of E. nuda was high compared to the ex vitro/natural conditions. This is the first report for in vitro propagation and tuberization of E. nuda. The protocol developed can be utilized for both large scale plant production and conservation of germplasm of this species. [Copyright &y& Elsevier]

Cadaba fruticosa (L.) Druce (Capparaceae) is a pharmaceutically valuable woody shrub. Reproductive constraints (poor seed-setting, low seed germination, viability, and seedling survival) coupled with habitat disruption have caused decline in populations of this now endangered species. This paper reports an improved de novo shoot organogenesis using mature leaf–derived callus for the first time. Influence of plant growth regulators (PGRs), incorporation of additives, amending salts, and re-culturing of differentiated callus on shoot multiplication in C. fruticosa were studied. About 77% of leaf explants produced yellow-green, proliferative, and organized callus from the cut-ends on Murashige and Skoog (MS) medium containing 1.0 mg L−1 of 2,4-dichlorophenoxyacetic acid (2,4-D). Leaf-derived regenerative callus optimally differentiated in multiple shoots on MS medium containing varied combinations of PGRs (0.25 mg L−1 kinetin [Kin], 0.5 mg L−1 6‑benzylaminopurine [BAP], and 0.1 mg L−1 α-naphthaleneacetic acid [NAA]). Anatomical analysis visualized meristematic centres (MCs) and emergence of meristemoids protuberances (MPs) from inoculated leaf explants. The incorporation of additives significantly enhanced shoot multiplication and promoted synchronous growth of shoot cultures. The leaf-derived callus showed 100% shoot differentiation and the highest number of shoots (48.61 ± 2.79) measuring shoot length (6.33 ± 0.43 cm) on POMAS (PGRs optimized medium with additives and salts) when differentiated callus was re-cultured for three passages. Hence, using the strategy of re-culturing the differentiated callus after harvesting shoots for six repeated passages, more than 200 shoots were obtained from 400 mg of callus. More than 83% of shoots exhibited ex vitro rooting after being pulse-treated (for 4 min) with 500.0 mg L−1 indole-3-butyric acid (IBA) and subsequently transferred to microbe-free Soilrite®, moistened with aqueous ¼ MS salts. The rooted plantlets were hardened under the greenhouse conditions with more than 82% survival. Thus, the method developed here can be an alternative approach for propagation and conservation of C. fruticosa germplasm. [ABSTRACT FROM AUTHOR]