U.S. Department of Agriculture: Agricultural Research Service, Lincoln, Nebraska
ORCID IDs
Date of this Version
2004
Citation
Crop Science, Vol. 44, November–December 2004
Abstract
96MD7413-58 (Reg. no. GP-773, PI 617069), 96MD7413-36 (Reg. no. GP-774, PI 617070), and 96MD7110-71 (Reg. no. GP-775, PI 617071) partial waxy (reduced amylose) hard winter wheat (Triticum aestivum L.) germplasm lines were released by the ARS, USDA, and the Nebraska Agricultural Experiment Station in November 2002.
These partial waxy wheats carry non-functional (null) alleles (Wx-A1b and Wx-B1b) at two of the three hexaploid wheat Wx loci. These loci encode isoforms of the enzyme granule-bound starch synthase (GBSS, EC 2.4.1.21), also known as the “waxy” protein. Wheats with nonfunctional alleles at two loci are known as “double-nulls.” Double-null partial waxy wheats produce endosperm starch with reduced amylose content, relative to that of single-null or wild-type wheats. Such starch confers unique functional properties to derived wheat flour. Suggested uses for partial waxy wheats include a novel source for the production of modified food starches, and a blending agent to create flours with optimal amylose concentration for the production of a variety of sheeted and baked food products (Epstein et al., 2002; Graybosch, 1998). Partial waxy wheats also are useful as donors of the Wx null alleles for the breeding of completely waxy (amylose free, triple null) lines. Crosses between double-null partial waxy wheats and completely waxy wheats will result in populations composed of 25%waxy individuals. In comparison, populations derived from crosses between wild-type wheat and waxy wheat will produce waxy progeny at a frequency of only 1/64.