Patents Examined by Gary Bension
  • Patent number: 5482857
    Abstract: The invention is a method for reproducing Douglas-fir by somatic embryogenesis using plant tissue culture techniques in a multistage culturing process. A suitable explant, typically the fertilized embryo excised from an immature seed, is first cultured on a medium that induces multiple early stage embryos. These are multiplied in a second culture having reduced growth hormones where the early stage embryos grow in size and vigor to advanced early stage embryos. The embryos may then be transferred directly to a cotyledonary embryo development culture containing an adsorbent such as activated charcoal. Preferably, they are first singulated by shaking in two or more liquid subcultures containing the adsorbent prior to placing them on the development medium. After several weeks somatic embryos having the appearance of zygotic embryos will have formed. These may be germinated before or after storage and transplanted to soil for further growth.
    Type: Grant
    Filed: February 25, 1994
    Date of Patent: January 9, 1996
    Assignee: Weyerhaeuser Company
    Inventors: Pramod K. Gupta, Gerald S. Pullman