2016 Volume 85 Issue 4 Pages 403-410
Four kinds of near-isogenic lines (NILs) of Japanese soft wheat with different compositions of high-molecular-weight glutenin subunits, which are controlled by Glu-A1 and Glu-D1 genes were cultivated with different amounts of nitrogen fertilizer applied at flowering time. Using their flour, the proportions of extractable polymeric protein (EPP), extractable monomeric protein (EMP) and unextractable polymeric protein (UPP) to total protein (EPP (%), EMP (%) and UPP (%)) were analyzed by size-exclusion high performance liquid chromatography. In a set of the lines carrying subunits 2+12 at Glu-D1 locus, UPP (%) was not significantly influenced by the presence or absence of the subunit at Glu-A1 locus. On the other hand, in a set of the lines carrying subunits 2.2+12 at Glu-D1 locus, EPP (%) and EMP (%) were increased and UPP (%) was reduced by the absence of the subunit at Glu-A1 locus. The increase in EPP, EMP, and UPP contents against the increase in flour protein content did not vary among the NILs, but in a set of the lines carrying subunits 2.2+12 at Glu-D1 locus, EPP content was greatly increased by the absence of the subunit at Glu-A1 locus, but the UPP content was not increased so much. In a set of the lines carrying subunits 2.2+12 at Glu-D1 locus, the increase in SDS sedimentation volume against the increase in flour protein content was significantly reduced by the absence of the subunit at Glu-A1 locus. This result may be explained by the differences between the increases in EPP and UPP content against the increase in flour protein contents. Thus, in the wheat carrying subunits 2.2+12 at Glu-D1 locus, introduction of a subunit at Glu-A1 locus is expected to improve the dough strength.
