Submitted to: Journal of Cereal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/2/2010
Publication Date: 5/24/2010
Publication URL: hdl.handle.net/10113/42028
Citation: Brevis, J.C., Morris, C.F., Manthey, F., Dubcovsky, J. 2010. Effect of the grain protein content locus Gpc-B1 on bread and pasta quality. Journal of Cereal Science. 51:357-365. Interpretive Summary: Quality traits are very important in wheat breeding programs due to higher standards set by millers, bakers, and consumers. Increased changes in dietary habits have resulted in a demand for wheat with specific quality characteristics to meet the processing requirements of diverse wheat-based foods. These food products include bread, cookies, and pastries made with common wheat (Triticum aestivum L.); and pasta made with durum wheat (T. turgidum ssp. durum L.). For both bread and pasta products, grain protein concentration (GPC) is a critical trait that affects their nutritional value and quality parameters. GPC is also a key parameter for market grading and classification and in most wheat growing regions high GPC wheat receives premium prices. In spite of its importance, GPC improvement in wheat breeding programs has been slow, likely due to its nature, environment, and the limited range of genetic variation controlling this trait in modern wheat cultivars. Wild emmer wheat, T. turgidum ssp. dicoccoides is one of the most promising species for expanding the genetic variation in GPC, and this journal article explores research in this area of GPC.
Technical Abstract: Grain protein concentration (GPC) affects wheat nutritional value and several critical parameters for bread and pasta quality. A gene designated Gpc-B1, which is not functional in common and durum wheat cultivars, was recently identified in Triticum turgidum ssp. dicoccoides. The functional allele of Gpc-B1 improves nitrogen remobilization from the straw increasing GPC, but also shortens the grain filling period resulting in reduced grain weight in many genetic backgrounds. We developed isogenic lines for the Gpc-B1 introgression in six hexaploid and two tetraploid wheat genotypes to evaluate its effects on bread-making and pasta quality. In common wheat, the functional Gpc-B1 introgression was associated with significantly higher GPC, water absorption, mixing time and loaf volume, whereas in durum wheat, the introgression resulted in significant increases in GPC, wet gluten, mixing time, and spaghetti firmness, as well as a decrease in cooking loss. On the negative side, the functional Gpc-B1 introgression was associated in some varieties with a significant reduction in grain size, test weight, and flour yield and significant increases in ash concentration. Significant gene × environment and gene × genotype interactions for most traits stress the need for evaluating the effect of this introgression in particular genotypes and environments.