Transfer of novel storage proteins from a synthetic hexaploid line into bread wheat

Pure line selection for the presence of Glu-D1-4t+10.1t in high molecular weight glutenin subunits was applied in a cross between a synthetic hexaploid wheat (SHW) 530-1 (Triticum dicoccum / Aegilops tauschii acc. 19088) (2n = 42, BBA(u)A(u)DDt) and two common wheat (T aestivum L.) cultivars `Albena' and Slaveya' (2n = 42, BBA(u)A(u)DD). Grain number and seed weight per plant of selected BC1 F5-7 individuals accompanied this high molecular weight subunit pair to create 9 wheat genotypes. They were tested in the field and showed sufficient germination and winter survival with high seed set. Hierarchical cluster analysis divided them in two groups (four in the first, including standard wheat cultivar Sadovska ranozreika-4' and six lines in the second cluster). The urea / SDS-PAGE method separated the new lines in two high molecular weight glutenin variants, Glu-A1-2*, Glu-B1-7+8, Glu-D1-4t+10.1t (8 genotypes) and Glu-Al -null, Glu-B1-7+8, Glu-D1-4t+10.1t (1 genotype), displaying equal low molecular weight glutenins. All families expressed two omega-gliadin bands: the gliadin #1 originated from SHW530-1, while #2 was transferred from wheat cultivar 'Albena'. The former one appeared to be the unique gliadin subunit in the genotypes, not expressed in both wheat parents. The incorporated high molecular weight glutenin alleles might serve as new genetic resources for improving the grain quality of modern common wheat.