“In vitro propagation of stone pine (Pinus pinea L). Molecular and physiological bases”<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

Ana Rodríguez, Candela Cuesta, Millán Cortizo, Belén Fernández and Ricardo Ordás

Área de Fisiología Vegetal. Dpto. Biología de Organismos y Sistemas. Instituto de Biotecnología de Asturias. Universidad de Oviedo. C/ Catedrático Rodrigo Uría, s/n E-33071 Oviedo (Spain)

 

Pinus pinea L. is one of the most important tree species of the Mediterranean area and is of great economical importance because of its edible pine nuts. The wide commercial potential of pine nuts ensures there is considerable motivation for the development of genetic breeding programs based on the identification of superior genotypes to establish clone banks. Unfortunately, conventional techniques of asexual propagation have not proved to be successful for P. pinea. Micropropagation is a suitable biotechnological technique for the mass clonal production of trees and in this article we review potential ways to micropropagate P. pinea.

    In conifers, adventitious shoot formation is induced by culturing cotyledon explants with cytokinins. The caulogenic model established for P. pinea cotyledons is a well characterized system for studying the control of in vitro shoot organogenesis at both the physiological and molecular level. Induction of the caulogenic process is controlled by dynamic biochemical pathways involving both exogenous and endogenous plant growth regulators, including uptake, distribution and metabolism of benzyladenine (BA), as well as the endogenous concentrations of active molecules (mainly cytokinins), within the cotyledons. Furthermore, in this report we describe the application of the suppression subtractive hybridization technique to identify early-induced genes during the first phases of adventitious caulogenesis in P. pinea. Most of the genes that are expressed in cotyledons after induction with BA could be associated with adventitious shoot development (Kumar and Sopory 2010).