Author
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TORBERT, KIMBERLY - UNIVERSITY OF MINNESOTA |
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Rines, Howard |
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SOMERS, DAVID - UNIVERSITY OF MINNESOTA |
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Submitted to: Oat International Conference Proceedings
Publication Type: Abstract Only Publication Acceptance Date: 8/6/1996 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: The oat (Avena sativa L.) transformation system as initially described utilizes friable, embryogenic callus tissue initiated from immature embryos of the GAF/PARK genotype as a source of totipotent target cells, and tissue cultures are generally used up to one year. Because often observed reduced fertility of regenerated transgenic plants may be due to an age effect in these cultures, we investigated methods to reduce the duration of the tissue culture period required to produce transgenic plants and to find a more convenient explant for tissue culture establishment. Mature embryos of GP-1 and two Minnesota lines were tested for tissue culture and transformation response. The frequency of GP-1 mature embryos that initiated embryogenic callus after being excised from presoaked seeds and placed on MS medium containing 2 mg/L 2,4-D was more than 50% after about 8 weeks. Starter-1 and MN89127 mature embryos exhibited 33% and 20% callus initiation frequency, respectively, but the callus initiated was primarily non-embryogenic. Twenty-one microprojectile bombardments of mature embryo derived callus from GP-1 yielded 68 paromomycin resistant tissue cultures. Seventy-one percent of the transgenic callus lines exhibited GUS expression. Plant regeneration frequency was 64%, a 28% improvement over results reported for immature embryo derived callus. The fertility of regenerated plants was greater than 90%. Overall, the mature embryo system output of fertile transgenic plants was more than double that of the immature embryo system. |
