MILLING AND BAKING QUALITY OF 1BL 1RS TRANSLOCATION WHEATS .1. EFFECTS OF GENOTYPE AND ENVIRONMENT/

Seven 1BL/1RS translocation wheats were compared with six control whea ts by standard tests used to assess milling and baking quality charact eristics. Test weight and 1,000-kernel weight were higher for wheats c ontaining the translocation. The flours of the translocation wheats we re of poorer quality, as shown by their lower protein content, weaker dough mixing strength, shorter dough extensibility, higher ratio of ex tensigraph resistance to extensibility, higher degree of dough stickin ess, and lower loaf volume. The translocation had no effect on kernel hardness, flour yield, farinograph absorption, dough development time, or mixograph development time. Growth environment had a marked effect on quality parameters. Group effects (1BL/1RS versus control wheats) were significant for all parameters except kernel hardness, flour yiel d, falling number, farinograph water absorption, and farinograph and m ixograph development time. The group-by-environment interactions were nonsignificant for most of the quality parameters. Wide variations amo ng cultivars or lines for physical, chemical, rheological, and baking characteristics were noted. Not all lines with the 1BL/1RS translocati on exhibited a high degree of dough stickiness. Three 1BL/1RS wheats ( 8416-Q06E, 8417-BJ03A, and 8417-BJ03D) were rated similar in quality t o the control wheat Biggar. Accordingly, they would be suitable for re gistration in the Canada Prairie Spring wheat class. None of the 1BL/1 RS wheats had quality characteristics suitable for the Canada Western Red Spring wheat class (i.e., equal in quality to Neepawa). Genetic ef fects were significant for all quality parameters. Environmental effec ts were significant for all quality characteristics except remix dough stickiness, kernel hardness, and mixograph band width at 2 min after the peak. Although the genotype-by-environment interactions were signi ficant, they were relatively small in magnitude for most of the qualit y characteristics. Remix dough stickiness was more highly correlated w ith quality characteristics than was first mix stage dough stickiness. Breadmaking quality decreased as the degree of remix stickiness incre ased. Stepwise multiple regression indicated that approximately 62% of the variability in the remix stickiness can be explained by protein c ontent and gluten strength.