Results of the second international winter wheat performance nursery

248 was derived from winter wheat grown in 1970 at 38 sites in 23 countries. Four of the sites were in the southern hemisphere. The same 39 varieties evaluated in the first nursery were grown in the second nursery. Twenty-eight varieties were winter wheats; two were spring wheats. Data on grain yield, test weight, maturity, plant height, lodging, shattering, winter survival, diseases, grain protein content and lysine content for 1970 are reported. Bezostaia again was the most productive variety over all reporting sites. It exhibited an unusually wide range of adaptation. Western European varieties as a group exhibited highly specific adaptation to the environments for which they were developed. Heine VII had the broadest adaptation among the Western European varieties. Hard red winter wheat varieties from the U.S.A. Bezostaia produced the highest test weight grain in the second nursery. Phenotypic expression of the high protein trait over diverse production environments was excellent. Lysine expressed as percent of protein was negatively correlated with protein. Varietal differences in maturity, plant height, lodging, disease resistance and other agronomic traits are discussed.