Plant regeneration of ilex paraguariensis (aquifoliaceaé) by in vitro culture of nodal segments

Abstract

In vitro regeneration of complete plants ffom nodal single bud segments of “yerba mate” {Ilex paraguariensis St. Hil.) was studied under defined nutritional and environmental conditions. Nodal segments harvested ffom actively growing shoots o f conventionally raised plants were cultured on nutrient médium with the mineral salts and vitamins o f Murashige and Skoog médium at 1/4 strength, supplemented with various concentrations o f sucrose and 6-benzyladenine (BAP). Shoot regeneration ffom explants o f both young (2 years oíd) and adult (20 years oíd) mother plants were readily achieved in the médium supplemented with 0.04 - 0.09 M sucrose with or without BAP. As many as 60 - 65% o f the nodal segments cultured formed shoots. Rooting o f regenerated shoots was observed in 50% o f the explants harvested ffom young plants, whereas 25% o f the explants rooted when the nodal explants were harvested ffom adult plants. The best rooting induction was achieved on 1/4 strength MS médium with vermiculite as the substrate and supplemented with 1 - 1.5% IBA (indolebutyric acid) and 1 - 2% PPZ (3- methyl - 1 - phenyl - 2 pyrazolin - 5 - one). Plantlets were successfully transferred to soil.