Two cultivars with a low amylose content, Kanto 107 (K107) and K79, we
re discovered in Japanese common wheat (Triticum aestivum L.). The amo
unt of Wx protein, identified as a single major starch granule-bound p
rotein of about 61 kD by sodium dodecyl sulfate polyacrylamide gel ele
ctrophoresis (SDS-PAGE), was greatly decreased in those two cultivars.
Analysis of their Wx protein with a modified SDS-PAGE and two dimensi
onal-PAGE showed that two of the three Wx proteins, produced by Wx-Al
and Wx-B1 loci, were not detected. It was thus concluded that only one
locus, Wx-D1, was active in the two low amylose cultivars. These muta
nts were termed ''partial waxy mutants'' and considered to be very use
ful material for breeding waxy wheat.