|Ivic, Snezana - USDA BA PSI BELTSVILLE MD|
Submitted to: American Society of Sugarbeet Technologists
Publication Type: Abstract Only
Publication Acceptance Date: December 28, 2001
Publication Date: N/A
Technical Abstract: A biolistic sugar beet transformation method (Snyder et al. 1999) was developed in this laboratory using embryogenic hypocotyl callus of a tissue culture clone REL-1. The feasibility of using this method with several commercially important sugar beet breeding lines was tested. We evaluated: 1) seed germination in vitro, 2) callusing and organogenesis of hypocotyl and cotyledon fragments on several media with different plant growth regulator compositions, and 3) influence of age of seedlings, hypocotyl color and position of explants on seedlings on calusing and regeneration. The best source of embryogenic callus for use in transformation experiments was achieved with commercial line C69. In 16 independent experiments, the original transformation protocol (Snyder et. 1999) was compared with seven other procedures that included varying the kanamycin concentration in the selection medium, length of selection and plant growth regulator composition in media used for cultivation of bombarded callus. Some of these treatments improved the shoot regeneration rate from hypocotyl and cotyledon callus, but most of the putative transformants were vitrified and did not develop into normal plants. Presence of the introduced gene was confirmed by PCR. This study showed that cotyledons of both the REL-1 and breeding lines were a good source of embryogenic callus for the particle bombardment method used to introduce beneficial foreign genes into sugar beet.