Variation of high molecular weight glutenin subunits in tetraploid wheat T. timopheevii

High molecular weight glutenin subunits present in several accessions of tetraploid wheats with genomic formula AAGG, T. limopheevii (cultivated) and subsp. araraticum (wild), were analyzed by sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) and reversed phase high performance liquid chromatography (RP-HPLC), Combination of these techniques permitted us lo associate different type of subunits to the A or the G genome and assess the extent of allelic variation present al corresponding encoding loci. Results also revealed thai in both subspecies accessions are present possessing expressed y- ­type subunits al the Glu-A 1 locus. This is in contrast wilh what was observed in tetraploid wheals of genomic formula AABB, where only in the wild species T. turgidum subsp. dicoccoides such subunit is expressed. Eleclrophoretic and chromatographic behaviour of x-and y-type subunits, present at the Glu-A 1 locus in both subspecies, is very similar to the one observed in the wild diploid wheat relative T. urartu. This result supports the role of this species in the formation of polyploid wheats of the timopheevii group.