Location: Wheat Health, Genetics, and Quality Research
2025 Annual Report
Objectives
This project is focused on enhancing wheat grain quality in the Western U.S. and elsewhere by providing the knowledge and means to breed better quality wheat varieties. We will achieve three primary objectives: 1) Resolve the underlying genetics of kernel texture (grain hardness), 2) develop wheat germplasm with lower and higher levels of starch amylose, and 3) collaboratively develop superior and novel wheat cultivars for the Western U.S. to ensure that millers and food processors have superior food ingredients, farmers grow high-value crops and consumers have appealing, nutritious and less expensive foods. Production of superior wheat cultivars makes the U.S. more competitive abroad and U.S. agriculture more sustainable. Objectives 1 and 2 are separated each into two Subobjectives, 1A involves the role of puroindolines, and other kernel texture loci derived from Aegilops tauschii, Extra-Soft, and Super-Soft germplasm. Subobjective 2B involves Granule bound starch synthase I and Starch branching enzyme IIa to reduce and increase amylose, respectively. Subobjectives 1B and 2B involve developing germplasm and genetic stocks with novel traits.
The above objectives represent multiple, interrelated issues of improving wheat quality, functionality, and marketability that have been identified by the PNW Wheat Quality Council over the last 20+ years during their annual collaborative tests. Project objectives and linkages among other projects that contribute to achievement of the overall project goal are illustrated in Figure 1. Guidance and input to the project plan come from a number of sources. Peer science guides the direction and evaluates the quality of much of the research on end-use quality traits. By synthesizing the needs of the end-use sector and state-of-the-art science, cutting-edge, relevant research is targeted. The result is embodied in Objectives 1 and 2, and the traits that will be studied. By extension and creativity, novel traits are envisaged and studied (e.g. ‘Super Soft’ kernel trait and soft durum). The outcome/products are improved cultivars that have superior and predicable end-use quality, genetic stocks, novel germplasm and new knowledge. In guiding the breeder line evaluation (Objective 3), the PNW Wheat Quality Council provides direct input from a large and representative number of end-users, cereal scientists, and stakeholders. New varieties are evaluated and discussed in an open forum. These discussions provide for establishing specific testing methodologies and strategies as well as specific target values.
Approach
Objectives 1 and 2: Extend our understanding of the role(s) of kernel hardness, puroindolines and other genes in wheat grain quality and utilization. Hypothesis: Different gene sequences of puroindoline a and b modulate different levels of kernel hardness; additional novel non-puroindoline genes/loci affect kernel texture. Extend our understanding of the role(s) of starch composition, including Waxy and high amylose genes on wheat grain quality and utilization. Hypothesis: Starch composition, i.e., amylose: amylopectin ratios can be manipulated via null mutations in GBSSI and SbeIIa; wheat with different starch composition provides novel processing and nutritional opportunities.
Puroindoline a, Puroindoline b and Grain softness protein-1 genes are sequenced. Aegilops tauschii and synthetic hexaploid wheats are obtained from germplasm collections. Synthetics are evaluated for kernel texture phenotype. Unique lines are crossed to Alpowa soft white spring wheat. The genetic basis for Extra-Soft and Super Soft genes hexaploid and durum germplasm will be determined. Develop germplasm and genetic stocks with unique starch biosynthesis genes. Develop, register and release spring wheat NILs for all eight haplotypes of GBSSI and SbeIIa; develop soft white winter wheat germplasm with the GBSS 4A null allele. The unique synthetics, backcross NILs, and starch mutants will be grown for milling and baking evaluations. Germplasm will be released and registered.
Contingencies: The experiments with synthetics are dependent on obtaining germplasm from the USDA and other repositories and having greenhouse space available. All other germplasm is currently housed in the WWQL. Successful crossing and plant growth, equipment being operational, etc. are essential. Marker density will need to be sufficient to detect the loci of interest. The effect of the environment on phenotypic expression of kernel texture will be addressed through replicated trials over two or more environments.
Objective 3: Evaluate and report the milling and end-use quality of PNW wheat under a Congressionally-designated direct mission of service, with the goal to develop and release new wheat cultivars to growers. Most tests follow AACCI Approved Methods. Standard methods include SKCS, Quadrumat milling, Solvent Retention Capacity, SDS sedimentation, Mixograph, cookie and bread baking.
Progress Report
This is the final report providing a summary of all the progress made on project 2090-43440-008-000D, titled, “Characterization of Quality and Marketability of Western U.S. Wheat Genotypes and Phenotypes” which has been replaced by new project 2090-30600-001-000D, titled, “Characterization of Quality and Marketability of Western U.S. Wheat Genotypes and Phenotypes.” This new project will focus on enhancing wheat grain quality in the Western U.S. and elsewhere by providing the knowledge and means to breed better quality wheat varieties.
Progress was made on all three Objectives, which fall under NP306.
In support of Objective 1, research utilized genetics to identify new commercial end-uses of Western wheat. Two major projects were undertaken to understand the impact of starch composition and chemistry of end-use quality. The first project was to create a large seed wheat ideal for creating a puffed snack or cereal. A waxy-wheat line was crossed with a large seeded soft durum to create a large seeded waxy wheat. Because waxy-wheat contains high levels of amylopectin and low levels of amylose, the starch is ideal for expanded products like puffed wheat. This new material will be ideal for creating a new product for snack and cereal manufacturers.
The second project in support of Objective 1 was using high amylose wheat to create a healthier ramen-style noodle. High amylose wheat is considered resistant starch in that it passes through the stomach and small intestine and is fermented by the large intestine similar to dietary fiber. This resistant starch can have major health benefits similar to dietary fiber. Ramen, or instant, noodles are a very popular food globally although they are not always the healthiest meal option. Using high amylose wheat blended with ‘normal’ wheat, high quality ramen noodles were made with more than double the amount of resistant starch, up to a level that would constitute a rating of “good source of dietary fiber.”
Additionally in support of Objective 1, several aspects of soft durum quality were examined using several different genetic introgressions and mapping populations. These introgressions included the strong gluten variant at the High Molecular Weight Glutenin Subunit (HMW-GS) Glu-D1 gene. These genes occur in hexaploid on the short arm of Chromosome 1D, and were introgressed into soft durum. There are HMW-GS on the A and B genome but those on the D genome have the greatest influence over gluten strength of all HMW-GS. The two haplotypes examined showed how gluten strength in soft durum could be modulated to “optimally strong” and “overly strong” for increased use of soft durum in a baking application.
In support of Objective 2, selected Recombinant Inbred Lines (RILs) nof Alpowa and Super Soft Alpowa (87.5% genetically similar) with kernel softness extremes were analyzed for proteomic changes at days 7, 14, and 28 following anthesis along with seeds at maturity. There were 175 differentially abundant proteins detected between the Soft and Super Soft lines across the four timepoints. Eighteen of the proteins were related to starch metabolism and five with lipids. Proteins associated with sucrose synthase differed between Soft and Super Soft lines, located in the 4B region of the wheat genome previously identified by ARS scientists at Pullman, Washington as being associated with the Super Soft trait. These findings solidified the genetic findings and demonstrated that the sucrose synthase pathway is likely involved in fine modulation of kernel softness.
For Objective 2, collaborative research with Washington State University resulted in advancement of High Amylose Cadenza lines by single seed descent (SSD) after the haplotypes were verified for the SBEIIa genes which control the amylose/amylopectin ratio in grain. These genes can be manipulated to produce a range amylose from high amylose to waxy wheat which possesses low or no amylose. These new lines allow us to explore novel uses of low/no amylose wheat such as puffing. A soft white spring wheat showing heterogeneity for the Waxy 4A allele was selected for the partial Waxy trait and progeny continued to be screened to verify the null 4A allele.
In support of Objective 3, ARS researchers in Pullman, Washington, evaluated and reported the milling (processing and intrinsic end-use quality) parameters of Western Soft White Common and Club (spring and winter), Hard Red Winter and Spring, and Hard White Winter and Spring Wheat commercially-viable germplasm as part of the Congressionally-designated direct mission of service (non-hypothesis driven). Annually, a total of ca. 6,000 experimental wheat germplasm and commercial cultivars were evaluated for breeding programs in the Western United States. In 2023 ARS researchers also started screening ca. 1,000 experimental pulse lines as part of a new service to U.S. pulse breeders annually.
Accomplishments
1. Arabinoxylan content was quantified for the lines entered by wheat breeders across the U.S. into the regional wheat trials. The content of arabinoxylan a major component of plant cell walls, is increasingly recognized as an important contributor to Total Dietary Fiber content of wheat. ARS scientists in Pullman, Washington, conducted the first large scale screening of United States wheat germplasm for arabinoxylan content. 28 samples from the Uniform Eastern trail, 40 samples from the Uniform Southern trial, 150 samples from the Southern Regional Performance trail, 108 samples from the Western Regional - Hard Wheat Performance trial, 104 samples from the Western Regional - Soft Wheat Performance trial, and 131 samples from the Northern Regional Performance Trial were evaluated using a rapid colorimetric method. The results showed a high level of genetic variation in arabinoxylan content. Those lines with higher levels of arabinoxylans can be used for more nutritious flour without changing the milling process. More nutritious wheat also adds value for growers to be able to grow grain with higher arabinoxylans and market that wheat with better nutritional properties for, potentially, a greater price.
2. Expansion of cultivar development testing services. Cultivar development testing services is a key component to the support provided to the wheat industry stakeholders in the Pacific Northwest (PNW). ARS scientists in Pullman, Washington, expanded the services beyond common wheat and conducted the first quality screening of Triticale samples at the USDA-ARS Western Wheat Quality Lab (WWQL). Twenty three Triticale and 12 durum samples from the University of California-Davis breeding programs were screened for general grain and flour quality tests. The triticale samples were evaluated, in particular, for gluten strength as a predictor of which lines could be selected for potentially high quality bread applications. The durum samples varied in Vitamin A content and the pasta quality was evaluated to ensure that the higher levels of Vitamin A did not disrupt the end-use quality of the durum. Additionally, the first large scale quality screening on cultivar development samples of intermediate wheatgrass material was conducted by ARS scientists. This included 17 genotypes screened for 24 grain, flour and baking quality tests. This intermediate wheatgrass has high levels of dietary fiber and the quality tests showed that some of the genotypes had strong potential for inclusion into baked goods for greater nutritional benefit.
3. Two new soft white wheat cultivars, ‘Sockeye CL+’ and ‘Piranha CL+’. Soft white winter wheat is the leading type grown in the Northwest United States. New varieties can provide producers with higher yields and lower risks associated with diseases. ARS scientists in Pullman, Washington, supported researchers at Washington State University to develop and release ‘Sockeye CL+’ and ‘Piranha CL+’, soft white winter wheat varieties. Sockeye CL+ and Piranha CL+ are two-gene Beyond Tolerant semi-dwarf varieties, meaning that they have naturally-occurring genetic mutations that allow tolerance to the Beyond herbicide for weed control while maintaining healthy wheat plants. The Beyond herbicide is an important tool for growers to maximize yield and the varieties that have Beyond tolerance are of great value for growers. They are broadly adapted to regions of Washington. Sockeye CL+ and Piranha CL+ have high grain yield and Sockeye CL+ has resistance to stripe rust, a major fungal pathogen. Sockeye CL+ and Piranha CL+ will provide producers an additional option for growing high yielding wheat in eastern Washington.
Review Publications
Richter, J.K., Saunders, S.R., Ikuse, M., Finnie, S.M., Ganjyal, G.M. 2024. Development of a novel pressure vessel system for the simulation of starch expansion – Methylated and regular waxy corn starch behave significantly different with and without cellulose inclusion. Starch. 77(1). Article 2300235. https://doi.org/10.1002/star.202300235.
Rottersman, M.G., Zhang, W., Zhang, J., Grigorean, G., Burguener, G., Carter, C., Vang, T., Hegarty, J., Zhang, X., Finnie, S.M., Dubcovsky, J. 2025. Deletion of wheat alpha-gliadins from chromosome 6D improves gluten strength and reduces immunodominant celiac disease epitopes. Theoretical and Applied Genetics. 138. Article 94. https://doi.org/10.1007/s00122-025-04882-3.
Daba, S.D., McGee, R.J., Finnie, S.M. 2025. Physicochemical, morphological, and digestibility properties of round and wrinkled pea starches. Cereal Chemistry. 102(3):611-627. https://doi.org/10.1002/cche.10880.
Daba, S.D., Panda, P., Aryal, U.K., Kiszonas, A., Finnie, S.M., McGee, R.J. 2024. Proteomics analysis of round and wrinkled pea (Pisum sativum L.) seeds during different development periods. Proteomics. 25(3). Article 2300363. https://doi.org/10.1002/pmic.202300363.
Daba, S.D., McGee, R.J., Kiszonas, A., Finnie, S.M. 2024. Characterization of starch fraction from wet protein isolation process in pea (Pisum sativum L.). Legume Science. 6(3). Article e242. https://doi.org/10.1002/leg3.242.
Carter, A.H., Balow, K.A., Shelton, G.B., Burke, A.B., Hagemeyer, K.E., Stowe, A., Wetzel, H., Neely, C., Steber, C.M., Chen, X., Kiszonas, A. 2025. Registration of 'Sockeye CL+' soft white winter wheat. Journal of Plant Registrations. 19(2). Article e70009. https://doi.org/10.1002/plr2.70009.
Carter, A.H., Balow, K.A., Shelton, G.B., Burke, A.B., Hagemeyer, K.E., Stowe, A., Wetzel, H., Neely, C., Steber, C.M., Chen, X., Kiszonas, A. 2025. Registration of ‘Piranha CL+’ soft white winter wheat. Journal of Plant Registrations. 19(2). Article e70010. https://doi.org/10.1002/plr2.70010.