Micropropagation of adult Stone Pine (Pinus pinea L.)

This paper describes a micropropagation protocol for in vitro propagation of mature Stone Pine trees. Axillary bud development was achieved by culturing bud explants in media containing various cytokinins. Experiments were conducted to test the effect of asepsis conditions, type and concentration of cytokinin and rooting protocol. Four cytokinins were tested, namely, benzyladenine, meta-topolin, N-benzyl-9-(2-tetrahydropyranyl)-adenine and thidiazuron (TDZ) of which TDZ gave the best results, as 59% shoot development was obtained following the application of 1 mu M TDZ to the culture medium. The shoot development was significantly influenced by the genotype of the tree, but was effective in explants from all 20 genotypes used in the trial. In vitro rooting was, however, difficult to achieve and could only be induced at low rates. This protocol represents the first successful biotechnological approach to the micropropagation of adult Pinus pinea trees.