Combination of Null, Variant, and Mutant Wx Alleles in Common Wheat Leads to Amylose Variations Ranging from Waxy to Normal. Issue 2 (1st March 2016)

• Record Type: Journal Article
• Authors: Yamamori, Makoto; Yasui, Takeshi
• Is Part Of: Crop science. Volume 56:Issue 2(2016)
• Page Start: 644
• Page End: 653
• Publication Date: 2016-03-01
• Subjects: Crop science -- Periodicals; Cultures -- Périodiques; Cultures de plein champ -- Périodiques; Crop science; Nutzpflanzen; Zeitschrift; Pflanzenbau; Periodicals; 633
• DOI: 10.2135/cropsci2015.07.0419
• Languages: English
• ISSNs: 0011-183X

Abstract

Abstract : The apparent amylose contents due to five variant or mutant Wx alleles ( Wx‐A1c, ‐A1i, ‐D1f, ‐D1 g, and ‐D1h ) in common wheat ( Triticum aestivum L.) were analyzed. The Wx gene encodes the granule‐bound starch synthase that produces amylose in grain starch. One wheat line was used for each Wx genotype and the genetic backgrounds of the lines were not identical. The wheat lines were ranked, from lowest apparent amylose content to highest, as follows: waxy Bandowase ( Wx‐A1b, ‐B1b, ‐D1b, abbreviated as bbb ), Tanikei A6599‐4 (bbf ), Wx‐A1i ( ibb ), Wx‐A1c ( cbb ), K107Afpp4 ( bbg ), Tanikei A6099 ( bbh ), Wx‐A1a ( abb ), Wx‐D1a ( bba ), and Bandowase ( aaa, normal amylose level: approximately 30%). The blue value and λmax of the lines were largely consistent with their rank based on apparent amylose content. A line carrying two variant alleles ( ibf ) produced an apparent amylose content between those of Wx‐A1i ( ibb) and Wx‐A1c ( cbb ), and a line with cbf produced an apparent amylose content between those of Wx‐A1c and Wx‐A1a ( abb ). Other studies have reported that five genotypes exist between abb and aaa . Although we used only one line for each genotype, the amylose contents of wheat developed using three null and five variant Wx alleles should range from waxy in bbb to normal in aaa with approximate continuity. The mutant allele Wx‐D1g carried a C‐to‐T mutation, which changed proline to leucine at the C terminus of the protein. This explains the decrease in amylose content caused by the Wx‐D1g allele.