Molecular characterization of waxy alleles in three subspecies of hexaploid wheat and identification of two novel Wx-B1 alleles

Theor Appl Genet. 2015 Dec;128(12):2427-35. doi: 10.1007/s00122-015-2597-7. Epub 2015 Aug 15.

Abstract

Two novel Wx - B1 null alleles that enlarge the genetic variability for this wheat gene were characterized, whose effects on wheat quality could be different to those of the Wx - B1b allele. The starch composition of wheat grain has a primary influence on flour quality. Wheat starch consists of two types of glucose polymers: amylose (22-35% of the total) and amylopectin (68-75% of the total). Amylose is synthesized by waxy proteins. Several studies have contributed to the catalogue of waxy alleles available for breeders, and the search for novel alleles of these and other proteins related to flour quality continues. In this report, we describe the characterization of two novel Wx-B1 alleles (Wx-B1k and Wx-B1m) in a collection of macha, Indian dwarf and club wheat. Several accessions lacking Wx-B1 protein were detected, and some were caused by the common Wx-B1b null allele. Of the other accessions, four from Indian dwarf wheat showed the insertion of 4 bp within the seventh exon, and one from club wheat had a deletion of four nucleotides in the second exon. These mutations were novel and provisionally catalogued as Wx-B1k and Wx-B1m, respectively, and could be used to enlarge the genetic variability for this gene.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles*
  • Amylopectin / chemistry
  • Amylose / chemistry
  • Base Sequence
  • DNA, Plant / genetics
  • Flour
  • Genes, Plant
  • Genetic Markers
  • Genetic Variation
  • Molecular Sequence Data
  • Mutation
  • Plant Proteins / genetics*
  • Sequence Analysis, DNA
  • Starch Synthase / genetics*
  • Triticum / classification
  • Triticum / genetics*

Substances

  • DNA, Plant
  • Genetic Markers
  • Plant Proteins
  • waxy protein, plant
  • Amylose
  • Amylopectin
  • Starch Synthase