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.