Variation and Covariation of Milling‐ and Baking‐quality Characteristics among Winter Rye Single‐cross Hybrids

Components of variation for, and genetic correlations among, measures of milling and baking quality were estimated for 38 winter rye single-crosses sown in three environments. Samples of grain were indirectly evaluated for baking quality via Falling Number and Amylograph tests whereas direct assessments of baking quality and milling yield were obtained from standardized Sourdough Baking tests and total flour release determinations, respectively. Estimates of genetic variation were large and highly significant (P < 0.01) for all traits whereas those of genotype × environment interactions were much smaller and often non-significant. Broad-sense heritability estimates were very high, ranging from 0.64 to 0.96. Crumb elasticity, the most important direct measure of baking quality, was significantly correlated with falling number (r g = 0.43) and Amylograph temperature at maximum viscosity (r g = 0.55). The dough yield, loaf volume and total flour release, however, showed no relation with the indirect measures of baking quality. The crumb elasticity was correlated positively with flour release but negatively with dough yield and loaf volume. Selection for high falling number would be an effective indirect method of increasing crumb elasticity. Enhancement of the other baking and milling characteristics would require direct measurements of the respective traits