Micropropagation of Pinus heldreichii

Micropropagation by organogenesis from mature embryos of Pinus heldreichii Christ. was achieved. The frequency of adventitious bud induction was higher on embryos grown on Gresshoff and Doy medium than on Von Arnold and Eriksson, or Murashige and Skoog medium. The greatest number of buds and developed shoots was obtained after induction with benzyladenine at 2.22 or 4.40 μM for four weeks. Shorter induction time was less effective for bud induction, but subsequent shoot elongation was accelerated. Shoots elongated on half-strength, growth regulator-free medium supplemented with activated charcoal. After pulse treatment with 1 mM indole-3-butyric acid twenty shoots were rooted, while agar-solidified medium supplemented with α-naphthaleneacetic acid (0.27 or 1.08 μM), or indole-3-butyric acid (0.25 or 0.98 μM) induced callus formation only. This revised version was published online in June 2006 with corrections to the Cover Date.