RESUMO

In Argentina, there are numerous native species which are an important source of natural products and which are traditionally used in medicinal applications. Some of these species are going through an intense extraction process in their natural habitat which may affect their genetic diversity. The aim of this study was to establish vegetative propagation systems for three native forestal species of medicinal interest. This will allow the rapid obtainment of plants to preserve the germplasm. This study included the following species which are widely used in folk medicine and its applications: Erythrina crista-galli or "seibo" (astringent, used for its cicatrizant properties and for bronchiolitic problems); Acacia caven or "espinillo" (antirheumatic, digestive, diuretic and with cicatrizant properties) and Salix humboldtiana or "sauce criollo" (antipyretic, sedative, antispasmodic, astringent). The methodology included the micropropagation of seibo, macro and micropropagation of Salix humboldtiana and the somatic embryogenesis of Acacia caven. The protocol for seibo regeneration was adjusted from nodal sections of seedlings which were obtained from seeds germinated in vitro. The macropropagation through rooted cuttings of "sauce criollo" was achieved and complete plants of this same species were obtained through both direct and indirect organogenesis using in vitro cultures. The somatic embryogenesis for Acacia caven was optimized and this led to obtain a high percentage of embryos in different stages of development. We are able to support the conservation of native forest resources of medicinal use by means of vegetative propagation techniques.

Assuntos

Acacia/crescimento & desenvolvimento , Conservação dos Recursos Naturais/métodos , Erythrina/crescimento & desenvolvimento , Plantas Medicinais/crescimento & desenvolvimento , Plantas Medicinais/genética , Salix/crescimento & desenvolvimento , Acacia/genética , Argentina , Erythrina/genética , Variação Genética , Salix/genética , Técnicas de Cultura de Tecidos/métodos

RESUMO

A highly efficient somatic embryogenesis system and subsequent plant regeneration of chinaberry (Melia azedarach L.) was developed. Plants were regenerated from indirect somatic embryogenesis induction. Novel features of this improved protocol, include: a) Embryogenic callus induction with no addition of 2, 4-D in the culture media; b) Somatic embryos differentiation was achieved by using high concentration of cytokinins (BAP 10 mg/L) and adenine; c) 100 percent conversion of somatic embryos to plants was practically obtained and 100 percent of plants survived under greenhouse conditions; d) Addition of putrescine improved somatic embryos germination. The amount of somatic embryos produced by the pathway of indirect somatic embryogenesis was 447 per gram of fresh weight callus. Regenerated plants were phenotypically normal. The developed protocol established the potential to produce plantlets from cotyledon explants through somatic embryogenesis. It also presents itself as a highly efficient method for mass clonal propagation and conservation of Melia azedarach.