Submitted to: Entomological Research (Korea)
Publication Type: Abstract Only
Publication Acceptance Date: 7/25/2007
Publication Date: 8/23/2007
Citation: Allen, M.L. 2007. Transgenic screwworm applications and SIT. Entomological Research (Korea). 37(1):A54; ISSN 1738-2297 (Print) ISSN 1748-5967 (online).
Technical Abstract: The New World screwworm, Cochliomyia hominivorax, presented unique challenges to transformation efforts. First, the eggs of this insect are deposited by the female on a warm-blooded host with an adhesive substance that must be removed. Embryological developement is complete after only nine hours under ideal conditions. The larvae thrive as a mass in culture, while small numbers of maggots fail to survive. Culture of the screwworm in the United States is permitted only in biological containment facilities. In 2002, the first successful screwworm transformation project produced eight transgenic strains. Each transgenic strain had unique genetic, phenotypic, and strain quality characteristics, and some strains were suitable for incorporation into the sterile insect technique (SIT) eradication program. The last U. S. screwworm culture facility was closed in 2004; fortunately, cryopreservation of transgenic screwworm germplasm was successful for four of the eight transgenic strains. These strains carry a fluorescent marker, and could be helpful in the sterile insect release program. Desirable traits for further improvement of the production of screwworms include inducible female lethality, preferably at an early stage of development, and inducible male sterility. Strategies for developing these strains are discussed. The identification of appropriate genetic materials to facilitate strain improvement is a continuing priority for the USDA ARS.