Effect of the genotype, explant source and culture medium in somatic embryogenesis and organogenesis in Vaccaria hispanica (Mill.) Rauschert

Vaccaria hispanica is an interesting species with attractive agronomic properties and a wealth of valuable bioactive compounds, potentially useful for many different purposes. Surprisingly, the number of studies focused on the development of in vitro tools for a rapid production of clonal populations is extremely limited. In the present study, two wild Turkish genotypes, previously characterized as high starch and saponin producers, are used to explore the possibilities of regenerating clonal plants through somatic embryogenesis and organogenesis. This work investigates the independent effects of genotype, type of explant and composition of the culture medium, and the interactions among them, in the growth and proliferation of calli from the explants, and the induction of somatic embryogenesis and organogenesis fron the callus surface. Some of the interactions were found significant to promote these processes. V. hispanica proved to be especially responsive for callus induction from all the explants tested. Particular explant types and combinations of plant growth regulators have been identified as especially suitable to induce the different morphogenic processes. V. hispanica is remarkably prone to produce thin adventitious roots, which may be a problem when trying to induce somatic embryogenesis or shoot organogenesis. However, this can be exploited to develop a convenient system for in vitro secondary metabolite production.