In vitro tuberization and plant regeneration from multinodal segment culture of Habenaria bractescens Lindl., an Argentinean wetland orchid

Abstract

Tuberization in many terrestrial orchids represents the most important physiological process for reproduction and survival. An in vitro controlled and reproducible tuberization and plant regeneration system was designed for Habenaria bractescens. Multinodal segments were incubated on Murashige and Skoog (MS) medium supplemented with different concentrations of N 6 -benzylaminopurine (BAP) and sucrose. After 45 days, the explants developed root tubers in vitro in 8 of the 12 media assayed. MS medium with 87.6 mM sucrose plus 4.4 lM BAP was one of the most effective for stimulating root tubers. Plants derived from in vitro root tubers were successfully transferred to the greenhouse without any acclimatization. The morphology and anatomy of the regenerated underground organs were examined to find identifying and distinguishing features. The protocol to regenerate root tubers of H. bractescens will be useful to study the basic aspects and control of tuberization and to carry out restoration programs.

In Vitro Mass Propagation of Ornamentally and Medicinally Important Coelogyne flaccida Lindl. through Pseudobulb Segments

“…Orchids are propagated in vitro by using various explants such as shoot meristem, leaves, roots, protocorms etc. obtained from axenic cultures but the regenerative potential of pseudobulbs as explants has been less explored as compared to the other explants (Morel 1960, 1970, Stewart and Button 1976, Vajrabhaya 1978, Shimasaki and Uemoto 1987, Arditti and Ernst 1993, George and Ravishankar 1997, Vij and Kaur 1998, Kanjilal et al 1999, Pyati et al 2002, Decruse et al 2003, Basker and Narmatha 2006, Martin 2007, Janarthanam and Seshadri 2008, Medina et al 2009, Sungkum and Deb 2009, Sunitibala and Kishor 2009, Hong et al 2010, Mata-Rosas et al 2010, Kaur and Bhutani 2010, Rajkarnikar 2011, Pant and Thapa 2012. Therefore, an attempt was made to establish an efficient regeneration system by using pseudobulbs as explants for C. flaccida in particular checking the (i) influence of maturity level of pseudobulbs on regeneration potential, (ii) suitable culture medium, and the effect of growth regulators individually and in combination on regeneration of the explants and their successive development into plantlets (iii) induction potential of the apical and basal segments.There is no report on the development of in vitro methodology for mass propagation of C. flaccida using different explants.…”

Microscopical analysis of in vitro Mokara Broga Giant orchids PLBs

“…Therefore, due to the existence of abundant meristematic tissues in PLBs, propagation of orchids using tissue culture techniques has been practiced for more than a century and has resulted in the production of uniform clones in many orchid genera. The formation of protocorms from germinated seed and the successive induction of protocorm-like bodies (PLBs) or callus from the protocorm, stem-node, shoot-tip, leaf, root-tip, or root-tuber explants has become a reliable technique for propagating orchids (Park et al, 2003;Anjum et al, 2006;Hong et al, 2008;Medina et al, 2009). Propagation through PLB formation is preferred by commercial growers of most orchid genera due to the large number of PLBs that can be obtained within a moderately short period of time.…”

In Vitro Regeneration of Shoots From Nodal Explants of Dendrobium Chrysotoxum Lindl

“…In this condition, use of alternative explants helps in raising innumerable genetically identical clones. So far, the regenerative potential of stemnodes has been positively tested in some orchid species (Arditti & Ernst 1993;George & Ravishankar 1997;Vij & Kaur 1998;Kanjilal et al 1999;Gangaprasad et al 2000;Pyati et al 2002;Decruse et al 2003;Basker & Narmatha Bai 2006;Martin 2007;Zhao et al 2007;Janarthanam & Seshadri 2008;Medina et al 2009;Rangsayatorn 2009;Hong et al 2010;Kaur & Bhutani 2010).Till date, in vitro propagation of D. chrysotoxum was reported only through seeds (immature/mature), shoot-tips and protocorm segments culture (Xu et al 2001;Roy et al 2007;Kaur & Bhutani 2011).The objective of this study was to access the regeneration competence of stemnodes to multiply the D. chrysotoxum by subjecting them to varying physical and chemical stimulus in the medium.…”