High Molecular Weight Glutenin Subunit Composition of Cultivars, Germplasm, and Parents of U.S. Red Winter Wheat

Abstract

Variation in high molecular weight (HMW) glutenin subunit composition is related to genotypic variation in wheat (Triticum aestivum L.) end‐use quality. No systematic survey of the HMW glutenin subunit composition of U.S. winter wheat has been conducted. The HMW glutenin subunit composition of 291 U.S. winter wheat cultivars, parental lines, and advanced experimental lines was determined by sodium dodecylsulfate‐polyacrylamide gel electrophoresis (SDS–PAGE). The most frequently observed subunits differed between soft red winter wheat (SRWW) and hard red winter wheat (HRWW). Most common subunits among SRWW were 1 (Glu‐A1), 7 + 8 (Glu‐B1), and 2 + 12 (Glu‐D1) and, among HRWW, 2* (Glu‐A1), 7 + 9 (Glu‐B1) and 5 + 10 (Glu‐D1). Examination of frequencies of subunits as a function of year‐of‐release (or introduction) revealed increases in the frequencies of subunits 7 + 9 and 5 + 10 in SRWW, and increases in the freqnencies of subunits 2*, 7 + 9 and 5 + 10 in HRWW. Decreasing frequencies of subunits 2 + 12, in SRWW, and subunits 1 and 2 + 12, in HRWW, were observed over time. The observed frequencies of deleterious (in terms of end‐use quality) and neutral alleles suggest the present HMW glutenin subunit frequencies are more dependent on random factors than on selection for enhanced quality characteristics.