In vitro regeneration using twin scales for restoration of critically endangered aquatic plant Crinum malabaricum Lekhak & Yadav: a promising source of galanthamine

This study intended to develop a significant in vitro regeneration protocol for sustainable propagation, conservation and re-establishment of critically endangered aquatic plant species Crinum malabaricum Lekhak & Yadav (Malabar river lily). This plant is the natural source of galanthamine, the drug to treat Alzheimer’s disease. We present a scientific understanding, emphasizing the use of twin scales (separated from the large parent bulb) in direct regeneration of new shoots and proliferation of bulblets assisted by nutrients supply. The meristematic region of the bulb plate, present between the scales was activated using cytokinins to produce shoots (maximum 12 shoots per twin scale) on full strength Murashige and Skoog’s (MS) medium augmented singularly with 2.0 mg L^?1 6-benzylaminopurine (BAP). Upon subculturing of shoots on diverse concentrations of plant growth regulators (BAP and IAA/NAA), BAP alone at 2.0 mg L^?1 was served optimum for the better proliferation of shoots (53 shoots). The regenerated shoots were rooted in vitro on half strength MS medium fortified with various types of auxins. Highest number of roots (11.6 within 4 weeks) and bulblets (after 3 months) resulted with 1.0 mg L^?1 Indole-3-butyric acid (IBA) under in vitro conditions. The rooted plants were hardened in the greenhouse and finally transferred to the natural stream with 83% survival rate. The SCoT (start codon targeted) and ISSR (inter simple sequence repeats) marker analysis of in vitro raised and mother plants confirmed the genetic stability of tissue cultured plants and the reliability of present protocol for C. malabaricum. It is the foremost report on in vitro regeneration and genetic fidelity analysis for restoration of this critically endangered aquatic plant using twin scale technique. The study could help in ex situ conservation, reintroduction and restoration of C. malabaricum population in its natural habitat.

     

Optimization of in vitro and ex vitro regeneration and micromorphological studies in <Emphasis Type="Italic">Basella alba</Emphasis> L.

The optimum concentrations of the plant hormones for in vitro regeneration and subsequent effect of auxins on rooting (in vitro and ex vitro) of shoots of Basella alba L. have been investigated in present study. Nodal shoot segments were used as explants to initiate the cultures. The bud breaking from explants was observed within 1 week of incubation on agar gelled Murashige and Skoog’s (MS) medium. Multiple axillary shoots (7.30 ± 0.56 shoots per explant) were induced on MS medium supplemented with 2.0 mg/L 6-benzylaminopurine (BAP). The shoots were multiplied (maximum 17.10 ± 0.44 shoots per explant) on the same medium fortified with 0.5 mg/L each of BAP and Kin (Kinetin) +0.1 mg/L IAA. These shoots were excised and rooted in vitro (10.73 ± 0.92 roots per shoot) on half-strength MS medium augmented with 2.0 mg/L indole-3 butyric acid (IBA). Hundred percentage success rates have been achieved by ex vitro rooting of the in vitro regenerated shoots with IBA at 300 mg/L. The in vitro and ex vitro rooted shoots were acclimatized in greenhouse and subsequently transferred to the natural field conditions where 100 % survival rate was reported. The ex vitro rooting method was found more advantageous than in vitro rooting in terms of time, energy and survival percentage of B. alba. A comparative foliar micromorphological study of B. alba was conducted to understand the micromorphological changes in plants while shifting from in vitro to the in vivo conditions in terms of variations in stomatal index, venation pattern and vein density, and the arrangement of crystals. The study could help in understanding the response of in vitro raised plants towards in vivo environment.     

Direct somatic embryogenesis using leaf explants and short term storage of synseeds in Spathoglottis plicata Blume

Plant Cell, Tissue and Organ Culture (PCTOC) - Spathoglottis plicata Blume is a vulnerable orchid species in various parts of the world, and the conventional propagation provides limited success to...     

Differential morphometric and micro-morpho-anatomical responses toward types of culture vessels used in micropropagation of Hemidesmus indicus (L.) R. Br.

Plant Cell, Tissue and Organ Culture (PCTOC) - Plantlets of Hemidesmus indicus (L.) R. Br. (Indian sarasaparilla) were developed in vitro in two different types of culture vessels and closure...