Agronomic and Quality Characteristics of High Protein F2‐derived Families from a Soft Red Winter‐Hard Red Winter Wheat Cross 1

PROTEIN content of the grain is a major quality factor in wheat. During 60 years of hard wheat breeding, little progress in the amount of protein synthesized in the wheat grain has been recorded. Two reasons are apparent. Known genetic differences in grain protein content among varieties of common wheat were small, whereas environmental effects were comparatively large (1, 2, 3). Distinctly superior genetic sources of high protein within Triticum aestivum were not identified until 1950 (7). Among the hard winter wheats, the variety Comanche was recognized for its comparatively high-protein grain and Wichita was established as one of the lower protein varieties. The difference between the two generally was less than 1% actual protein. The soft winter wheat variety Atlas 66 was introduced into the Nebraska breeding program in 1953 as a new source of leaf rust resistance and high protein. It was used in crosses with both Wichita and Comanche. In 1954, the North Carolina Agricultural Experiment Station reported that Atlas 66, a high-yielding variety, produced significantly more protein in its grain than other soft winter wheat varieties of equal yield with which it was compared (7). Beginning in 1953, Atlas 66 was compared with Wichita, Comanche, and other hard winter wheats at locations in the southern part of the hard red winter wheat region to establish whether it produced more protein in its grain than the hard winter varieties. During a 3-year period of testing, Atlas 66 consistently produced more protein than Wichita and Comanche but was significantly lower yielding than the last 2 varieties in most trials. Whether the protein superiority of Atlas 66 would persist when its yield was equal to these varieties could not be established conclusively. Later trials in Oklahoma and Texas in 1957 in which Atlas 66 was as productive as Wichita and Comanche clearly demonstrated that Atlas 66 produces grain with higher protein content than these hard winter wheats when yields are comparable (5). Agronomic relations and inheritance of high protein in wheat have been studied extensively in the greenhouse and