The effect of cultivar, environment, and their interactions on soft red winter wheat (Triticum aestivum L.) quality has never been determinated in the southeastern United States. In this study, 22 soft wheat cultivars and 2 hard wheat cultivars were grown in 12 southeastern environments in a randomized complete block design having two replications. Flour yield, whole grain protein percent, particle size index, and alkaline water retention capacity were measured. Highly significant differences were detected among environments and cultivars for each of the quality variables. The cultivar ✕ environment interaction was highly significant for all variables. Cultivars with good soft wheat quality and good stability were identified. The cultivar means from an environment were generally highly significantly correlated with the regional cultivar means indicating that for preliminary quality evaluations, data from one environment is sufficient for ranking cultivars.

Kernel density, a component of test weight, is not associated with variety when considering Eastern soft wheats Triticum aestivum L. em Thell. (aestivum group), but seems to be related to environment. Air spaces within the grain appear to be a major factor in determining kernel density.Packing efficiency (the percent of bulk volume occupied by grain), the second component of test weight, is associated with variety. Grain shape and surface characteristics such as humping, dorsal or lateral depressions, and wrinkling, cause variations in void space ratio; hence they directly affect random packing efficiency.These conclusions were based on results with normal, well‐filled grain; any appreciable shriveling of grain confounds varietal and environmental effects.

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The effect of powdery mildew (Erysiphe graminis DC. f. sp. tritici E. Marchal) infection on yield, and milling and baking quality was determined under natural field conditions. Near‐isogenic lines of ‘Chancellor’ wheat (Triticum aestivum L.), involving at least seven independent genes for resistance to powdery mildew, were grown at College Park and Queenstown, Md. in 1974 and 1975. A regression equation was determined to predict the effects of disease severity on yield.The severity of powdery mildew infection varied among years and locations. Chancellor yielded 34% less than the average yield of the resistant lines. Yield was negatively correlated with percent powdery mildew on the whole plant and on the flag leaf (r = ‐0.78** and −0.80**, respecively). The regression equation of yield in q/ha (Ŷ) on percent powdery mildew on the flag leaf was Y = 33.4 − 0.18 X, r2 = 0.65**. The gene in ‘Michigan Amber’ and the three Pm 3 genes were highly effective in reducing infection.The isolines differed significantly for percent flour protein, cookie diameter, and adjusted cookie diameter when grown under severe powdery mildew infection. The lines with the highest disease rating also had the lowest flour protein content. Percent flour protein was negatively correlated with percent powdery mildew on the whole leaf and the flag leaf (r = −0.77** and −0.80**, respectively). However, severe powdery mildew infection did not adversely affect the over‐all baking quality. Milling quality (flour yield and flour ash percent) was not affected by the severity of powdery mildew infection.

Test weight is defined as the weight of grain that fills a given volume. It is the product of kernel density and volume of grain occupying the container. The latter component, when expressed as percentage of the volume of the container, is referred to as packing efficiency and was shown to be a cultivar characteristic. Of the two components packing efficiency has a greater effect on test weight when comparing soft winter wheats (Triticum aestivum L. em Thell).There was a negative correlation between test weight and the kernel length‐width ratio (kernel shape). When the length‐width ratio remained constant, there was no increase in test weight when kernel volume increased. Kernel width was correlated more than length with kernel volume. Test weight and flour yield were not correlated within or among cultivars. Kernel protein was related to kernel size within cultivars.