Embryogenic Tissue Initiation in Loblolly Pine (Pinus Taeda L.)

  • Gerald S. PullmanEmail author
Part of the Forestry Sciences book series (FOSC, volume 84)


Somatic embryogenesis (SE) technology has the potential to be the lowest-cost method to rapidly produce large numbers of high-value seedlings with desired characteristics for plantation forestry. SE is expected to play an important role in the future to increase forest productivity, sustainability and uniformity. SE technology has the advantages of: (1) shortening time to produce desired Planting stock, (2) allowing control of genetic variation,  (3) permitting commercial hybrids, and  (4) facilitating genetic engineering efforts for desirable traits. Conifer SE proceeds through four steps: initiation, multiplication, maturation and germination and cryopreservation when storage of cultures is desired. This report will focus on the initiation step. When research began, initiation rates for loblolly pine were often below 1%. Early improvements occurred through combinations of optimal embryo stages, half-strength P6 salts, ovule osmotic profile research, modeling activated carbon (AC) uptate of 2,4-D and research to understand the effect of pH and  AC on mineral availability. Many improvements in loblolly pine initiation over the past 30 years have resulted from careful study of the developing seed and embryo. Medium supplements and environmental conditions are available to improve imitiation and somatic embryo development that have resulted from analytical studies of seed tissues, the seed environment and gene experssion in the megagametophyte, zygotic embryos and somatic embryos.   



I thank the Institute of Paper Science and Technology at Georgia Tech (Renewable Bioproducts Institute) and its member companies for providing funding, materials and supplies and a home for this research over the past 24 years. Without plant materials from forest companies including Arborgen, Boise Cascade, Georgia Pacific, MeadWestvaco Corporation, Union Camp, Westvaco and Weyerhaeuser NR Company this research could not have been done. I also thank the Georgia Institute of Technology, State of Georgia TIP3 Program, and the Consortium for Plant Biotechnology Research (DOE Prime Agreement No. DEFG36-02GO12026 and USEPA grant EM-83438801) along with member companies Arborgen, Monsanto Company and Weyerhaeuser Company for financial support. In addition, I am grateful for the valuable assistance of Michael Buchanan, Kylie Bucalo, Dr. John Cairney, Kelly-Marie Chase, Xiaorong Feng, Shannon Johnson, Dr. Sheldon W. May, Jonathan Mein, Paul Montello, Kavita Namjoshi, Anna Skryabina, Xiaoyan Zeng and Yalin Zhang.


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© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of Biological SciencesRenewable Bioproducts Institute, Georgia Institute of TechnologyAtlantaUSA

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