Location: Wheat Health, Genetics, and Quality Research
2017 Annual Report
Objectives
The long-term objective of this project is to improve wheat quality, functionality and marketability in the Western U.S. Specifically, during the next five years we will focus on the following objectives:
Objective 1: Resolve the underlying genetics of end-use quality traits, and identify useful genetic variation to produce predictable and new end uses.
• Sub-objective 1A: Extend our understanding of the role(s) of kernel hardness and puroindoline genes in wheat grain quality and utilization.
• Sub-objective 1B: Extend our understanding of the role(s) of starch composition and waxy genes on wheat grain quality and utilization.
Objective 2: Increase the value and global competiveness of U.S. commercial wheat by enabling new technologies and methods to accurately assess end-use functionality; and to manipulate wheat fiber and antioxidant components to improve grain and flour quality.
• Sub-objective 2A: Develop a model system for identifying putative grain flavor loci/genes in wheat.
• Sub-objective 2B: Manipulate grain arabinoxylan content to improve flour quality, nutrition and utilization.
Objective 3: Congressionally designated as a direct mission of service, and non-hypothesis driven, the USDA-ARS Western Wheat Quality Laboratory will identify, evaluate, and screen the intrinsic end-use quality to enhance cultivar development.
Approach
Objective 1A: Puroindoline a, b, and Grain softness protein-1 genes are amplified from genomic DNA via PCR and sequenced, followed by alignments and phylogenetic analyses. Aegilops tauschii accessions are obtained from germplasm banks. Unique haplotypes are identified in synthetic hexaploid wheats and evaluated for kernel texture. Soft durum lines derived from Soft Svevo will be increased and receive complete milling and baking analyses. Kernel texture variation in the RIL population derived from Butte 86 x ND2603 will be mapped. Kernel texture variation referred to as “Super-Soft” will be mapped using an Alpowa Super-Soft derivative. RILs will be developed using single seed descent. Contingencies: Marker density will need to be sufficient to detect linkage disequilibrium. If a particular chromosome or arm has low polymorphsism, then additional markers will be added.
Objective 1B: Full waxy and partial waxy lines will be developed in Stephens, Xerpha, and MDM varieties. Waxy progeny are identified with I2/KI. Partial waxy lines are identified using PCR markers. NILs will be developed in a BC7F2 population using marker assisted selection. The 4A-null lines will be evaluated for Japanese Udon noodle. Full waxy lines will be evaluated in twin barrel extrusion.
Objective 2a: A system that uses a common check variety will be developed. Hollis (yummy) and ID703 (yucky) were used to make a DH mapping population. DH line vs. check t-values will be used as the phenotypes for mapping. Mapping will be employed to identify candidate genes/QTLs for consumption preference. Contingencies: Different ‘check’ varieties may be needed depending on the relative preference/avoidance. If the QTLs from one check variety do not fully agree with the QTLs from the second check variety, then a third intermediate preference variety will be evaluated. If LOD scores are not sufficiently large, then a sub-set of lines with contrasting consumption preference will be evaluated with a larger number of mice.
Objective 2b: Yumai 34 and Alpowa have high arabinoxylan (AX) content, whereas Louise has low levels. DH populations from Yumai 34 x Louise, Yumai 34 x Alpowa, and Alpowa x Yumai 34 were produced. These populations will be milled and baked, and evaluated by Solvent Retention Profiles and Bostwick viscosity. Total AX, water extractable AX (WE-AX), and arabinose to xylose ratio will be analyzed via GC-FID. All the DH lines will be genotyped with markers. Lines with contrasting high and low AX contents, high and low ratios of WE-AX vs. water unextractable, and high and low ratios of arabinose substitution will be identified. These traits will be compared with end-use quality phenotypes and will be analyzed via molecular markers. Contingencies: We will identify the ‘best’ choices for full AX analyses based on contrasting end-use quality traits. If there is not a ‘consensus’ among traits, then contrasting phenotypes will be selected for individual traits.
Objective 3: Testing and evaluation of experimental wheat breeding germplasm follows standard testing protocols, including Approved Methods of AACCI and AOAC. Tests include grain, milling, flour and end-products tests.
Progress Report
Progress was made on all three objectives and their subobjectives, which fall under ARS Strategic Plan Goal 1 (Nutrition, Food Safety, and Quality), Performance measure 1.1.3 (Develop methods and technologies to better define, measure, preserve or enhance quality and improve utilization of food crops, animals and agricultural fibers). This research will address several problem areas, products, and outcomes identified in the NP 306 Action Plan, namely; Component 1 (Foods) Problem 1.A (Define, measure, and preserve/enhance/reduce attributes that impact quality and marketability).
Under Objective 1a, the USDA ARS collection of Aegilops tauschii was obtained and the sequencing and haplotyping of Puroindoline a, Puroindoline b, and Grain softness protein-1 was completed and phylogenetic analyses are underway. Soft Svevo and Svevo durum wheat were grown at multiple locations, grain samples were sent to collaborators in France where they were analyzed for milling and compositional analysis, and a manuscript with those results was published. The ND2603 x Butte 86 hard red spring wheat population was grown, analyzed for kernel hardness phenotype and Genotyping-by-Sequencing (GBS) was performed. The data were analyzed and a manuscript was drafted. F2 plants of an ‘Alpowa Super-Soft’ by ‘Alpowa’ cross were harvested and the next inbreeding (single seed descent) generation was grown in the greenhouse.
Under Objective 1b, Waxy Stephens, Xerpha and MDM winter wheat germplasm were grown in the greenhouse and backcrossed to the recurrent parent; full waxy progeny were selected. A BC7F2 waxy Alpowa population was grown and the progeny were haplotyped for waxy genes using PCR; a complete set of Granule Bound Starch Synthase gene combinations have been isolated.
Under Objective 2a, a hard by soft white winter wheat cross Clark’s Cream x NY6418 population was evaluated in our mouse model system using Yummy (Y) and yucky (y) controls, and the results were evaluated using the t-test as a consumption phenotype; a manuscript describing the results was published (ARIS log #338243).
Under Objective 2b, a Yumai 34 x Louise doubled haploid spring wheat population was grown in the field, and submitted to the regional genotyping lab for analysis. Instrumentation for analyzing arabinoxylans is currently unavailable.
Under Objective 3, we are completing the final milling and baking analyses for the 2016 harvest for wheat breeding samples; data have been distributed to breeders and plans for the 2017 harvest are in place.
Accomplishments
1. Soft kernel durum wheat is a new bakery ingredient for food processors and a new raw material for pasta. Currently, durum wheat production and utilization are limited by its very hard kernel texture, which restricts its culinary uses. An ARS scientist in Pullman, Washington, in cooperation with Washington State University researchers, has determined the milling and baking quality of durum wheat varieties with soft kernel texture. The research indicated that soft kernel trait reduced flour particle size and starch damage; milling performance was highly similar to soft white wheat. This research adds to the body of technical information regarding the performance and end-use applications of soft durum wheat, thus assisting millers and bakers in commercialization.
2. Mice prefer Yummy (Y) wheat grain. Whole grain wheat foods can provide critical nutrients for health and nutrition in the human diet, but undesirable flavors limit consumption. The house mouse is highly discriminating in what wheat varieties it prefers to eat, and thus is being used as a model system to investigate the genetic basis of wheat flavor. Flavor genes can be identified using genetic mapping, and a consumption “phenotype”. ARS scientists in Pullman, Washington, in cooperation with a Washington State University researcher, identified flavor loci in two-sample feeding trials. This novel approach to genetic mapping showed that flavor preference could be used to conduct genetic mapping. This research that identified both better and worse tasting genes will help identify wheat varieties to use in human sensory panels, and facilitate the identification of the underlying genetics associated with flavor differences, better tasting wheat may result.
Review Publications
Wu, G., Ross, C.F., Morris, C.F., Murphy, K.M. 2017. Lexicon development, consumer acceptance, and drivers of liking of quinoa varieties. Journal of Food Science. 82:993-1005.
Fleischman, E.F., Kowalski, R.J., Morris, C.F., Nguyen, T., Li, C., Ganjyal, G., Ross, C. 2016. Physical, textural, and antioxidant properties of extruded waxy wheat flour snack supplemented with several varieties of bran. Journal of Food Science. 81:E2726-E27233.
Lottes, O.C., Kiszonas, A., Fuerst, E.P., Morris, C.F. 2016. Wheat grain consumption and selection by inbred and outbred strains of mice. Physiology and Behavior. 165:154-158.
Murray, J.C., Kiszonas, A., Wilson, J.D., Morris, C.F. 2016. Effect of soft kernel texture on the milling properties of soft durum wheat. Cereal Chemistry. 93:513-517.
Kiszonas, A., Fuerst, E.P., Talbert, L., Sherman, C.F., Morris, C.F. 2016. Effect of wheat (Triticum aestivum L.) seed color and hardness genes on the consumption preference of the house mouse (Mus musculus L.). Mammalia. 80:655-662.
Ibba, M.I., Kiszonas, A., Morris, C.F. 2017. Definition of the low molecular weight glutenin subunit gene family members in a set of standard bread wheat (Triticum aestivum L.) varieties. Journal of Cereal Science. 74:263-271.
Kiszonas, A., Morris, C.F. 2016. Identifying genetic markers of wheat (Triticum aestivum) associated with flavor preference using a mouse model. Journal of Cereal Science. 71:153-159.
Ibba, M., Kiszonas, A., Morris, C.F. 2017. Evidence of intralocus recombination at the Glu-3 loci in bread wheat (Triticum aestivum L.). Theoretical and Applied Genetics. 130:891-902.
Heinze, K., Kiszonas, A., Murray, J.C., Morris, C.F., Lullien-Pellerin, V. 2016. Puroindoline genes introduced into durum wheat reduce milling energy and change milling behavior similar to soft common wheats. Journal of Cereal Science. 71:183-189.
Murray, J.C., Kiszonas, A., Morris, C.F. 2017. The influence of soft kernel texture on the flour, water absorption, rheology, and baking quality of durum wheat. Cereal Chemistry. 94:215-222.
Kiszonas, A., Boehm, J.D., See, D.R., Morris, C.F. 2017. Identification of SNPs, QTLs, and dominant markers associated with wheat flavor preference using genotyping-by-sequencing. Journal of Cereal Science. 76:140-147.
