Micropropagation, seed propagation and germplasm bank of Mandevilla velutina (Mart.) Woodson

Abstract

Mandevilla velutina (Mart.) Woodson (Apocynaceae) is a medicinal plant species with antivenom properties, native from Brazilian Savanna regions (Cerrado), which due to overexploitation and habitat deforestation is in danger of extinction. As an initiative for conserving this endangered but economically important plant species, a micropropagation protocol was developed and genotypes were stored in the Germplasm Bank "Cerrado In vitro". For the in vitro propagation of M. velutina, nodal segments were inoculated on Murashige and Skoog (MS) medium supplemented with different concentrations of BA, Zeatin, 2ip, DTT and TDZ. Best multiplication ratio was achieved when to the medium 0.44 μM BA, ranging 1: 6.7, were added. Plantlets cultured on MS/2 medium supplemented with 26.85 μM NAA rooted successfully (50.5%). Although rooted and un-rooted plantlets acclimatized to soil conditions, great losses were observed within un-rooted plantlets, while the rooted presented 100 % survival. It was possible to maintain 43% of the M. velutina germplasm under healthy conditions for six months, with no subcultures, using the MS medium supplemented with 2% sucrose, 13.8 mM spermidine, 2% sorbitol and 2% dextrose.

Micropropagation and callogenesis in Mandevilla guanabarica (Apocynaceae), an endemic plant from Brazil

“…This medium, indicated for woody plants, has lower concentration of nutrients than the salt composition of MS, with 25% of the nitrate and ammonia contained in LS and MS, but with high concentrations of potassium and sulfate (Linsmaier and Skoog 1965). Studies on the micropropagation of other Mandevilla species obtained positive results with LS medium ( Handro et al 1988) and MS medium with the concentration of salts reduced to one-third (Biondo et al 2004, Biondo et al 2007. Similarly superior results with diluted media were obtained here for M. guanabarica.…”

“…Shoot production by direct organogenesis via the development of preexisting meristems was observed in all treatments with cytokinins. TDZ cytokinins, which are a potent regulator and more active than BA and Zea, and 2-iP have been recommended for micropropagation in order to induce axillary bud development and shoot elongation (Pereira-Netto 1996, Biondo et al 2007). High rates of shoot multiplication were obtained, by direct organogenesis, with the same concentrations used here, 0.49 and 2.46 µM 2-iP for M. illustris (Biondo et al 2004), and for other species of Apocynaceae, such as Holarrhena antidysenterica, with 15 µM 2-iP (Raha and Roy 2001).…”

“…With M. velutina, multiple shoots were obtained using combinations of BA-NAA (Handro et al 1988) or BA in the range of 0.44 to 4.44 µM, with a maximum multiplication rate of 1:6.7; Zea, TDZ and 2-iP were not effective in producing shoots of this species (Biondo et al 2007). …”

“…In these studies with Mandevilla, rooting was improved by the addition of auxins to the culture medium; the best results were obtained with NAA and IBA for M. illustris and M. velutina (Handro et al 1988, Biondo et al 2007, and IAA and IBA for M. moricandiana (Cordeiro et al 2012). For M. guanabarica, WPM B without plant growth regulators allowed 100% rooting, which was fundamental for successful acclimatization.…”

“…These species have an underground system that is widely used in folk medicine in the form of infusions or alcoholic extracts, against inflammation and snakebite (Calixto et al 1985). For optimizing the production of secondary metabolites with pharmacological properties from the underground system of Mandevilla species, micropropagation protocols have been established, using in vitro culture techniques (Handro et al 1988, Biondo et al 2004, Biondo et al 2007). …”