CULTURE OF PINUS RADIATA EMBRYOS WITH REFERENCE TO ARTIFICIAL SEED PRODUCTION

Embryos excised from mature Pinus radiata D. Don seeds were cultured in a small volume of a nutrient medium contained in a small aluminium capsule to form an artificial seed. The embryos developed with normal morphology, although not as large as those from natural seeds. All plants from artificial seeds formed roots in sterile soil. The growth of embryos placed radicle-down into the same agarified-medium was inferior in that the lengths of cotyledons, hypocotyls, and roots of the resulting plants were all markedly reduced. When embryos were cultured in liquid medium, development was aberrant, with virtually no root growth. Nutrient supply through the (natural) cotyledonary route appeared to be superior to entry through roots or hypocotyl