GENETIC IMPROVEMENT OF PRODUCTIVITY AND NUTRITIONAL QUALITY OF WHEAT

This final evaluation covers the period 7/66-12/79; no methodolgy is specified. Analyses of 20,000 cultivars in the USDA"s World Collection and in Nebraska showed that genetic variation for protein (P) of at least 5 percentage points exists in hexaploid wheat; genetic variation for lysine (L) amounts to only 0.5 percentage points; L, as a percent of P, correlates negatively with P at P levels up to 15%; and a strong positive correlation exists between L per unit weight and grain P content. Major genes affecting grain P content were identified in Atlas 66 and Nap Hal. Genes modestly effecting L were found in CI13449 and Nap Hal. Hybridized genes were successfully transferred to productive short-statured winter and spring wheats. High yield varieties (HYV"s) developed included Lancota (a hard winter variety), Sava and Partizanka (Yugoslavia), Kavkaz and Aurora (U.S.S.R.), and Centurk (Nebraska). Genetic studies indicate that Atlas 66 carries two or more major genes for P. Genetic increases in L provided by CI13449 and Nap Hal, while limited, are great enough for use in breeding programs and for overcoming the depression of L % of P due to P elevation. Laboratory procedures were developed to streamline the large-scale screening of P and L samples. Tests showed that Atlas 66 and its high P derivatives, when consumed whole-grain, are significantly more nutritional than ordinary wheat. Significant associative nitrogen fixation could not be shown for Nebraska wheat. An international winter wheat evaluation network, involving 68 test sites in 38 countries, has been effective in early identification of new, stable, and broadly adaptable winter HYV"s. Nineteen students associated with the project (seven from LDC"s) received Ph.D. (13) or M.S. (6) degrees. Ten researchers from seven LDC"s received non-degree training. Some 544 researchers in 46 countries received high-protein L germplasm upon request. Four international wheat conferences and an international workshop on seed P were held and their proceedings distributed.