Tissue culture methods for the clonal propagation and genetic improvement of Spanish red cedar (Cedrela odorata)

The choice of a method to culture red cedar tissues depends on the final objectives pursued. If homogeneous clonal material is required for experimental purposes, the easiest way is to generate the lines through adventitious shoot induction from seedlings germinated from seeds. If the objective is to generate high yielding material for plantation purposes, the choice will be the same method but starting from mature vegetative tissues from selected elite plants. Most of the process are the same, but the initial steps are less efficient and much more elaborate. If the purpose is to generate lines with new genetic characteristics through somaclonal variation, mutagenesis, or genetic transformation, somatic embryogenesis will be required. No single method in its present form is suitable for all purposes. Eventually, the efficient production of somatic embryos from rejuvenated shoots collected from mature selected plants is the ideal way to culture this species, but for the time being we have to choose one or the other. In this chapter, we present a grafting procedure to rejuvenate and maintain mother plants in the greenhouse and the in vitro culture systems we have developed for the production of Cedrela odorata propagules using explants from both young seedlings and mature tissues from selected old trees. Using a modified TY17 medium and the BioMINT(®) temporary immersion system, we obtained high multiplication and ex vitro transplantation rates for efficient large-scale propagation of this species.