Quantitative Trait Loci Associated with Milling and Baking Quality in a Soft × Hard Wheat Cross

Hybridization between soft and hard wheat creates new associations among loci. Advantages include an increase Interclass hybridization between soft and hard wheat (Triticum in genetic diversity, a potential increase in grain yield, aestivum L.) results in new genetic combinations of potential value. and transfer of pest resistance genes. Both May et al. We investigated whether interclass hybridization could improve enduse quality of both classes. Our objectives were to analyze quality (1989) and Carver (1996) indicated that recovery of soft traits in a population of recombinant inbred lines (RILs) derived from or hard wheat quality characteristics was possible in a cross between the good quality soft white wheat NY6432-18 (NY18), interclass single crosses if genetic variation for grain and good quality hard white wheat Clark’s Cream (CC), identify quality was maintained at a high level within the segrequantitative trait loci (QTLs) for those traits, and use linkage analysis gating population. A better understanding of the underto determine which parent was contributing favorable alleles at spe- lying genetic structure influencing wheat quality would cific QTLs for a given trait. The population was assessed for milling, hasten the development of unique wheats possessing protein and dough mixing, hydration, cookie and loaf traits. Traits value-added traits as well as wheats suited to convenwere measured in two to six environments grown over three seasons tional end-uses. Specifically, we wondered if interclass in Ithaca, NY. The molecular map for the population contains 370 hybridization could create new associations among loci molecular markers including restiction fragment length polymorthat would actually improve end-use quality of both phisms (RFLPs), microsatellites, and markers derived from known function genes in wheat. Linkage groups have been located to all the hard and soft wheat. wheat chromosomes except for 7D. Pinb derived from the puroindo- Wheat flour is classified for use in baking on the basis line b gene on chromosome 5DS was the major QTL for milling, of its texture (soft vs. hard) and chemical properties hydration, and cookie baking traits. The major QTL for mixograph (primarily protein). In the USA, the main use of hard peak time was at the Glu-Dy1 marker, derived from Glu-D1-2 gene wheat flour is for bread baking and the main use of on chromosome 1DL. The Glu-Ax1 and Glu-By1 markers were QTLs soft wheat flour is for cookie baking. Cookie flour is for mixograph peak height and tolerance, respectively. QTLs for flour characterized by low water absorption, fine particleprotein quantity were detected on chromosome 2B. With the excep- size, and low protein content as compared with bread tion of the hydration traits, multiple regression models included alleles flour milled from hard wheat (Hoseney, 1988). During from both parents. Interclass hybridization may be an underexploited the initial milling step, soft wheat endosperm fractures wheat breeding strategy for improvement of agronomic and quality through cell walls and hard wheat endosperm fractures traits in wheat. at the cell wall. As a consequence, soft wheat flour particles are finer than those in hard wheat flours. Sub