'Plant Breeding: Sustaining the Future' Abstracts of the XVIth EUCARPIA Congress, Edinburgh, Scotland, 10-14 September 2001 ANALYSIS OF TETRAPLOID WHEAT BAC CLONES CARRYING GENES ENCODING SEED STORAGE PROTEINS AND STARCH BIOSYNTHESIS ENZYMES Y.Q. GU, X. KONG, D. COLEMAN-DERR, R. CHIBBAR, J. DOBCOVSKY, O. ANDERSON USDA/ARS/WRRC, 800 Buchanan Street, Albany, CA 94710, USA

Wheat quality is primarily determined by the genes encoding the seed storage protein and starch biosynthesis enzymes.  Therefore, knowledge of the structure of these genes is important for genetically engineering grain improvements.  Using 4 seed storage protein and 8 starch biosynthesis enzyme probes, we screened a cultivated tetraploid wheat (Triticum turgidum var. durum) BAC library. Between 4 and 40 positive clones were obtained for each of the single-copy starch biosynthesis genes.  238, 74 and 96 positive clones were recovered for the α-gliadin, γ-gliadin  and low-molecular-weight glutenin (LNW-glutenin) genes, respectively, which are known to belong to large gene families.  Fingerprint analysis will be performed to assemble the BAC contigs for loci containing these three seed storage protein genes, enabling us to determine their complexity in the wheat genome.