Soft White Wheat Research Articles

Impacts of Whole-Grain Soft Red, Whole-Grain Soft White, and Refined Soft White Wheat Flour Crackers on Gastrointestinal Inflammation and the Gut Microbiota of Adult Humans.

Consumption of whole-grain wheat has been associated with positive health outcomes, but it remains unclear whether different types of wheat elicit varying effects on the gut microbiome and intestinal inflammation. The objectives of this research were to investigate the effect of two whole-grain wheat flours versus refined wheat flour on the diversity of the human gut microbiota, as well as on butyrate production capacity and gastrointestinal inflammation, using one-week dietary interventions. For this study, 28 participants were recruited, with ages ranging from 18 to 55 years and a mean BMI of 26.0 kg/m2. For four weeks, participants were provided 80 g daily servings of different wheat crackers: Week A was a run-in period of crackers made from soft white wheat flour, Week B crackers were whole-grain soft white wheat flour, Week C crackers were a wash-out period identical to Week A, and Week D crackers were whole-grain soft red wheat flour. At the end of each week, participants provided fecal samples that were analyzed for markers of intestinal inflammation, including lipocalin and calprotectin, using enzyme-linked immunosorbent assays and quantitative real-time PCR. The primary outcome, gut bacterial community alpha and beta diversity, was similar across timepoints. Three taxa significantly differed in abundance following both whole-grain wheat flour interventions: Escherichia/Shigella and Acidaminococcus were significantly depleted, and Lachnospiraceae NK4A136 group was enriched. Secondary outcomes determined that protein markers of intestinal inflammation and genes related to putative butyrate production capacity were similar throughout the study period, with no significant changes. Lipocalin concentrations ranged from 14.8 to 22.6 ng/mL while calprotectin ranged from 33.2 to 62.5 ng/mL across all 4 weeks. The addition of wheat crackers to the adult human subjects' usual diet had a minimal impact on their gastrointestinal inflammation or the gut microbiota.

Yield has minimal effect on whole-grain mineral density of modern soft wheat compared to production environment, genotype, and test weight

ProblemMillions of people worldwide lack diversified diets and rely on staple foods, like wheat, that are inherently poor in minerals as primary sources of nutrition. Efforts have been made to enhance grain mineral density in wheat through plant breeding and crop management, though there is concern that mineral “dilution” will occur if higher yield is also sought. Much of that concern comes from studies comparing historic and modern wheat genotypes with impactful genetic differences (e.g., tall vs. semi-dwarf), but there is much less clarity in studies focused on modern genotypes. ObjectiveThe objective of this research was to better understand factors affecting concentrations of eight minerals in whole-grain soft white wheat, especially yield. MethodsThis was done by collecting a genetically and environmentally diverse grain mineral dataset and analyzing it in multiple ways. ResultsThere was no significant effect of yield on density of any tested mineral in grain when factors such as production environment and test weight were controlled, though regression coefficients for yield were generally negative. Thus, the negative effect of yield was present, but it was insignificant and small relative to other sources of variation. Production environment had the greatest impact on grain minerals, contributing between 50% and 90% of variation in the data, depending on the mineral. Wheat genotype had an impact on density of most minerals and genotype by environment interactions were common. Achieving genetic gain in elevating grain minerals through plant breeding may be most successful for Zn, P, and Mg, because genotypic variation and heritability were relatively high for these minerals. Further analysis of Zn showed that breeding selection for simultaneously high-Zn, high-yield wheat varieties is possible, because individual wheat varieties tended to have consistent grain Zn relative to the mean, regardless of yield level or production environment. Grain test weight also had a significant impact on concentrations of two minerals (K and Cu). Factors that impact plant health and metabolism, and ultimately grain test weight, are likely to also affect plant mineral uptake and translocation, possibly causing this association. ImplicationsIn summary, this analysis provides evidence that the impact of yield on grain mineral density among modern wheat germplasm is small and insignificant. In the quest to improve the mineral nutrient value of wheat through plant breeding, crop management, and other approaches, the minor negative impact of yield should be considered secondarily to much more significant factors like production environment, wheat genotype, and even test weight.

Comparison of intrinsic allergenicity potentials of gliadins from durum and soft white wheats in an adjuvant-free mouse model

Abstract Wheat is one of the major allergenic foods capable of eliciting life-threatening anaphylaxis. Discovering potential hypo/hyper-allergenic wheat classes is imperative to advance our knowledge and manage wheat allergy. Durum wheat (genome AABB) and soft white wheat (genome AABBDD) are two commonly consumed wheats. However, whether there are differences in the intrinsic allergenicity potential between them is unknown. Here, we tested the hypothesis that gliadins extracted from durum and soft white wheats will differ in their intrinsic allergenicity in an adjuvant-free mouse model that uses skin sensitization followed by intraperitoneal (IP) allergen challenge. Balb/c female mice were produced and maintained on a plant protein-free diet during this study. Groups of mice (n=5–10/group) were exposed to gliadins or vehicle via the skin once a week for 9 weeks. IgE responses were analyzed by ELISA to determine sensitization. Systemic anaphylaxis upon IP challenge was quantified by hypothermic shock response (HSR); mucosal mast cell response (MMCR) was quantified by measuring MMCP-1 in the blood. Our results suggest that mice exhibited robust, but comparable levels of specific IgE antibody responses after skin exposures to both wheat gliadins elicited. HSRs induced upon IP challenges with gliadins from the two wheats displayed strikingly similar kinetics. Interestingly, soft white wheat gliadin was significantly more potent in eliciting MMCR compared to the durum wheat gliadin. We demonstrate for the first-time the similarities and differences in intrinsic allergenicity potentials of gliadins obtained from the two wheats. Supported by grants from USDA/NIFA Hatch Project MICL02486 (Accession Number: 1012322)

Evaluation of salt-soluble protein extract from an ancient wheat progenitor (Aegilops tauschii) for intrinsic allergenicity in an adjuvant-free mouse model of wheat allergy

Abstract Wheat allergies are a growing significant health concern around the globe. The ancient diploid wheat progenitor, Aegilops tauschii (genome DD), contributed to the genetic diversity of the common soft white wheat (Triticum aestivum, genomes AABBDD). The allergenic potential of Ae. tauschii is largely unknown. Here we tested the hypothesis that the the salt-soluble protein extract (SSPE) from Ae. tauschii will be intrinsically allergenic in an adjuvant-free mouse model of wheat allergy. The ancient wheat progenitor was grown at the Michigan State University greenhouse using the seeds stored at our wheat breeding program. The SSPE was prepared, characterized for quality, and then tested in the mouse model that uses skin sensitization followed by oral allergen challenge. Balb/c mice were produced and maintained on a plant protein-free diet. Groups of adult mice (n=10/group) were repeatedly exposed to SSPE or vehicle via the skin. Allergic sensitization was assessed by specific IgE (sIgE) response. Oral anaphylaxis was quantified by hypothermic shock response (HSR). The mucosal mast cell response (MMCR) was quantified by measuring MMCP-1 in the blood. Repeated skin exposure to SSPE but not the vehicle elicited robust sIgE response. Oral SSPE challenge but not vehicle challenge elicited significant, but a modest HSR as well as MMCR. In summary, we report the characterization of intrinsic allergenicity potential of the SSPE obtained from the Ae. tauschii wheat progenitor for the first time. Funding: USDA/NIFA. The United States Department of Agriculture (USDA)/National Institute of Food and Agriculture (NIFA); Hatch project MICL02486 (Accession Number: 1012322); Hatch project MICL01699; Agricultural and Food Research Initiative Competitive Program, grant number: 2018-67017-27876

Registration of ‘Runde’ spring bread wheat cultivar

Abstract‘Runde’ (Reg. no. CV‐1201, PI 702366; S02147‐7H‐0N‐2H‐0N) soft white spring bread wheat (Triticum aestivum L.) cultivar was developed by Crop Breeding Institute and released in December 2016 through the National Variety Release Committee. Runde was selected from a cross between S98066‐7H‐0G‐1H‐0N and F99012 made in 2002 at Harare Research Station. S98066‐7H‐0G‐1H‐0N is an experimental line made from a cross between F97009 (International Maize and Wheat Improvement Center [CIMMYT] line) and SC91155‐4H‐0G‐0H‐0G‐6G‐0N (Crop Breeding Institute line). F99012 is an experimental line developed by CIMMYT. Runde (S02147‐7H‐0N‐2H‐0N) is a product of a 2002 cross made in Zimbabwe as cross no. 147, using the pedigree method. Runde is an early maturing, rust tolerant, and high yielding cultivar. It is generally large‐seeded (49 g/1000 grains). The genotype was among the best performing cultivars with tolerance to rusts due to the presence of leaf rust and stem rust resistance genes, Lr34, Sr2, and Lr68. It has high flour extraction potential, good dough mixing characteristics, and high flour concentration.

Detection of T-2 Toxin in Wheat and Maize with a Portable Mass Spectrometer

T-2 toxin is a mycotoxin routinely found as a contaminant of cereal grains worldwide. A portable mass spectrometer was adapted to enable the detection of T-2 toxin in wheat and maize by APCI-MS. In order to facilitate rapid testing, a rapid cleanup was used. The method was able to detect T-2 toxin in soft white wheat, hard red wheat, and yellow dent maize and could be used to screen for T-2 at levels above 0.2 mg/kg. The HT-2 toxin was only detectable at very high levels (>0.9 mg/kg). Based on these results, the sensitivity was not sufficient to allow the application of the screening method to these commodities at levels recommended by the European Commission. With a cut-off level of 0.107 mg/kg, the method correctly classified nine of ten reference samples of wheat and maize. The results suggest that portable MS detection of T-2 toxin is feasible. However, additional research will be needed to develop an application sensitive enough to meet regulatory requirements.

Cover Image, Volume 16, Issue 3

On the cover: ‘Cameo’ club wheat has resistance to multiple biotic and abiotic stressors and is best adapted to northeastern Oregon, northern Idaho, and eastern Washington. See K. Garland‐Campbell et al., “Registration of ‘Cameo” soft white winter club wheat,” https://doi.org/10.1002/plr2.20234. Photo by Kimberly Garland‐Campbell. image

Registration of ‘Cameo’ soft white winter club wheat

AbstractSoft white club winter wheat (Triticum aestivum L. ssp. compactum) is an important component of soft white wheat production in the Pacific Northwest of the United States. Most of the current club wheat production is in the <350 mm annual precipitation zone in central Washington, but there is interest in club wheat in the Palouse region of the United States (the counties of Whitman and Garfield in Washington and in Latah County in Idaho). Growers are continuing to grow the older club wheat cultivars ‘Cara’ and ‘Coda’, and there is a need for a new winter club wheat targeted to this region. ‘Cameo’ club wheat (Reg. no. CV‐1192, PI 699960), tested as ARS09X492‐6CBW, with awned spikes and soft white kernels, was developed using the bulk‐pedigree breeding method from the cross ARSC96059‐2/IL01‐11934//ARSC96059‐2‐0‐16. Cameo has better agronomic performance than other club wheat cultivars in trials on the Palouse, better stripe rust resistance than the club wheat ‘ARS Crescent’, tolerance to several major biotic and abiotic stressors, consistent good grain volume weight, mid‐season maturity and moderate height, excellent club wheat quality, and tolerance to low falling numbers. Cameo is not as competitive for grain yield in the traditional club wheat growing area in central Washington but is well suited to increasing the acreage of club wheat in the Palouse region of Idaho and Washington.

From Bread to Cake

Abstract This article deepens our understanding of Cold War–era agricultural history by examining the relationship between Pacific Northwest soft white wheat and Japanese importers and consumers. Recent historiography of wheat during the Cold War has focused on telling how the United States turned to wheat exports in the “developing world” as a tool and weapon to achieve US hegemony and negate the influence of the Soviet Union. This article argues that the Pacific Northwest wheat industry's relationship with wheat consumers and importers in Japan shifts the Cold War wheat narrative away from staples like bread to confectionary products made with soft white flour. Japanese buyers and consumers purchased soft white wheat not to feed the hungry but instead to serve a growing market for cakes and other confectionary products. This relationship helps understand the current wheat market in the Pacific Northwest, where soft white wheat exports dominate.

Physicochemical Properties of Washed Wheat Bran

Wheat bran, a by-product of roller milling during the milling process of wheat, contained substantial amounts of residual starch that may interfere with the analysis of bran’s physicochemical properties. The main objectives of this study were to develop a method that removed away most of the starch adherent to milled wheat bran and to investigate the effects of washing on the physicochemical properties (such as water binding capacity) and composition (including insoluble dietary fiber, soluble dietary fiber, total dietary fiber) of washed and non-washed wheat bran. Soft white wheat bran was washed with distilled water at room temperature and mixed with a modified Servodyne mixer to wash residual starch away from bran. The bran-starch slurry was transferred into a SoyCow presser lined with a filter cloth and rinsed to remove as much starch as possible. The washed and non-washed bran samples were dried overnight at 60°C and ground to pass through 1000 or 425 µm screens. Washing was significantly reduced starch adherent to wheat bran by 76% (w/w), a changed the contents of insoluble dietary fiber and soluble dietary fiber from 39 to 69% (w/w) and from 4.93 to 1.68% (w/w), respectively. Water binding capacity was higher for washed bran and was not affected by bran particle size. The transition onset and peak temperatures of washed wheat bran samples were significantly higher than the counterpart values of non-washed bran samples. On the other hand, transition enthalpies of washed bran samples were lower than those of non-washed bran samples.

Genetic architecture of end-use quality traits in soft white winter wheat

BackgroundGenetic improvement of end-use quality is an important objective in wheat breeding programs to meet the requirements of grain markets, millers, and bakers. However, end-use quality phenotyping is expensive and laborious thus, testing is often delayed until advanced generations. To better understand the underlying genetic architecture of end-use quality traits, we investigated the phenotypic and genotypic structure of 14 end-use quality traits in 672 advanced soft white winter wheat breeding lines and cultivars adapted to the Pacific Northwest region of the United States.ResultsThis collection of germplasm had continuous distributions for the 14 end-use quality traits with industrially significant differences for all traits. The breeding lines and cultivars were genotyped using genotyping-by-sequencing and 40,518 SNP markers were used for association mapping (GWAS). The GWAS identified 178 marker-trait associations (MTAs) distributed across all wheat chromosomes. A total of 40 MTAs were positioned within genomic regions of previously discovered end-use quality genes/QTL. Among the identified MTAs, 12 markers had large effects and thus could be considered in the larger scheme of selecting and fixing favorable alleles in breeding for end-use quality in soft white wheat germplasm. We also identified 15 loci (two of them with large effects) that can be used for simultaneous breeding of more than a single end-use quality trait. The results highlight the complex nature of the genetic architecture of end-use quality, and the challenges of simultaneously selecting favorable genotypes for a large number of traits. This study also illustrates that some end-use quality traits were mainly controlled by a larger number of small-effect loci and may be more amenable to alternate selection strategies such as genomic selection.ConclusionsIn conclusion, a breeder may be faced with the dilemma of balancing genotypic selection in early generation(s) versus costly phenotyping later on.

Multi-Trait Multi-Environment Genomic Prediction for End-Use Quality Traits in Winter Wheat.

Soft white wheat is a wheat class used in foreign and domestic markets to make various end products requiring specific quality attributes. Due to associated cost, time, and amount of seed needed, phenotyping for the end-use quality trait is delayed until later generations. Previously, we explored the potential of using genomic selection (GS) for selecting superior genotypes earlier in the breeding program. Breeders typically measure multiple traits across various locations, and it opens up the avenue for exploring multi-trait–based GS models. This study’s main objective was to explore the potential of using multi-trait GS models for predicting seven different end-use quality traits using cross-validation, independent prediction, and across-location predictions in a wheat breeding program. The population used consisted of 666 soft white wheat genotypes planted for 5 years at two locations in Washington, United States. We optimized and compared the performances of four uni-trait– and multi-trait–based GS models, namely, Bayes B, genomic best linear unbiased prediction (GBLUP), multilayer perceptron (MLP), and random forests. The prediction accuracies for multi-trait GS models were 5.5 and 7.9% superior to uni-trait models for the within-environment and across-location predictions. Multi-trait machine and deep learning models performed superior to GBLUP and Bayes B for across-location predictions, but their advantages diminished when the genotype by environment component was included in the model. The highest improvement in prediction accuracy, that is, 35% was obtained for flour protein content with the multi-trait MLP model. This study showed the potential of using multi-trait–based GS models to enhance prediction accuracy by using information from previously phenotyped traits. It would assist in speeding up the breeding cycle time in a cost-friendly manner.

An Intervention With Michigan-Grown Wheat in Healthy Adult Humans to Determine Effect on Gut Microbiota: Protocol for a Crossover Trial.

BackgroundDaily fiber intake can increase the diversity of the human gut microbiota as well as the abundance of beneficial microbes and their metabolites. Whole-grain wheat is high in fiber.ObjectiveThis manuscript presents a study protocol designed to understand the effects of different types of wheat on gastrointestinal tract microbes.MethodsHuman adults will consume crackers made from three types of wheat flour (refined soft white wheat, whole-grain soft white wheat, and whole-grain soft red wheat). In this study, participants will alternate between crackers made from refined soft white wheat flour to those made from whole-grain soft white wheat and whole-grain soft red wheat flour. Survey and stool sample collection will occur after 7-day treatment periods. We will assess how wheat consumption affects gastrointestinal bacteria by sequencing the V4 region of 16S rRNA gene amplicons and the inflammatory state of participants’ intestines using enzyme-linked immunosorbent assays. The butyrate production capacity of the gut microbiota will be determined by targeted quantitative real-time polymerase chain reaction.ResultsWe will report the treatment effects on alpha and beta diversity of the microbiota and taxa-specific differences. Microbiota results will be analyzed using the vegan package in R. Butyrate production capacity and biomarkers of intestinal inflammation will be analyzed using parametric statistical methods such as analysis of variance or linear regression. We expect whole wheat intake to increase butyrate production capacity, bacterial alpha diversity, and abundance of bacterial taxa responsive to phenolic compounds. Soft red wheat is also expected to decrease the concentration of inflammatory biomarkers in the stool of participants.ConclusionsThis protocol describes the methods to be used in a study on the impact of wheat types on the human gastrointestinal microbiota and biomarkers of intestinal inflammation. The analysis of intestinal responses to the consumption of two types of whole wheat will expand our understanding of how specific foods affect health-associated outcomes.International Registered Report Identifier (IRRID)DERR1-10.2196/29046

Twin-screw extrusion characterization of two varieties of soft white waxy wheat flours

Two soft white varieties of waxy wheat flours, Waxy Penawawa and Waxy Alpowa, were extruded with different moisture contents (MC), screw speeds (SS), temperatures, and screw profiles (SPs) to identify differences in their extrusion characteristics. An attempt was also made to compare them with a regular non-waxy wheat flour. No significant difference was identified between the two varieties of soft white wheat used. However, it was found that the soft white waxy wheat flour had the potential to have radial expansion ratios that were similar to non-waxy varieties (>4.0) with relatively less specific mechanical energy input (approximately 200 kJ/kg). Extrusion of soft white waxy wheat varieties was found to be more cost-effective when compared with the extrusion of conventional wheat flour extrusion.

Environment characterization and genomic prediction for end‐use quality traits in soft white winter wheat

AbstractEnd‐use quality phenotyping is laborious and expensive, thus, testing may not occur until later generations in wheat breeding programs. We investigated the pattern of genotype × environment (G × E) interaction for end‐use quality traits in soft white wheat (Triticum aestivum L.) and tested the effectiveness of implementing genomic selection to optimize breeding for these traits. We used a multi‐environment unbalanced dataset comprised of 672 breeding lines and cultivars adapted to the Pacific Northwest region of the United States, which were evaluated for 14 end‐use quality traits. Genetic correlations between environments based on factor analytic models showed low‐to‐moderate G × E interaction for most traits but high G × E interaction for grain and flour protein. A total of 40,518 single‐nucleotide polymorphism markers were used for genomic prediction. Genomic prediction accuracies were high for most traits thereby justifying the use of genomic selection to assist breeding for superior end‐use quality in soft white wheat. Excluding outlier environments based on genetic correlations between environments was more effective in increasing genomic prediction accuracies compared with that based on environment clustering analysis. For kernel size, kernel weight, milling score, ash, and flour swelling volume, excluding outlier environments increased prediction accuracies by 1–11%. However, for grain and flour protein, flour yield, and cookie diameter, excluding outlier environments did not improve genomic prediction performance.

Registration of ‘ARS Crescent’ soft white winter club wheat

AbstractSoft white club winter wheat (Triticum aestivum L. ssp. compactum) represents 8–10% of the wheat crop in Washington, but most of the current club wheat production is located in the <350‐mm annual precipitation zone. Our goal was to develop a club wheat cultivar targeted to the >350‐mm annual precipitation zones of the Pacific Northwest. ‘ARS Crescent’ (Reg. no. CV‐1181, PI 665048), an awned white‐kernel club wheat, was selected using the bulk‐pedigree breeding method from the cross ‘Dusty’//‘Madsen’ sib/Dusty///WA7665/‘Rulo’. At the time of release, ARS Crescent was rated as resistant to stripe rust races PSTv‐4 and PSTv‐51, segregating for resistance to race PSTv‐37, and susceptible to races PSTv‐14 and PSTv‐40 in the seedling stage. In the adult‐plant stage in the field, ARS Crescent has demonstrated high‐temperature adult plant resistance to stripe rust. Several years after release, the grain yields of ARS Crescent are equivalent to the club wheat ‘Bruehl’ and to soft white wheat checks for all growing regions. ARS Crescent combines better test weight than Bruehl with better resistance to environmental conditions that result in low falling numbers in wheat. ARS Crescent has excellent milling properties and greater sponge cake volume than other club wheat cultivars and increases the quality of the crop in Washington.

Registration of ‘Castella’ soft white winter club wheat

AbstractSoft white winter club wheat (Triticum aestivum L. ssp. compactum) is a specialty class of soft wheat prized for its end‐use quality. Our goal was to develop a broadly adapted club wheat cultivar targeted to the U.S. Pacific Northwest (PNW) with competitive agronomic and end‐use quality characteristics. ‘Castella’ (Reg no. CV‐1185, PI 695319), a tall semi‐dwarf awnless white‐kernel club wheat, was selected using the bulk‐pedigree breeding method, from the cross NY89‐66‐7131//B980696//‘Chukar’. In the seedling stage, Castella is resistant to PSTv‐51 and PSTv‐40 but susceptible to races PSTv‐4, PSTv‐14, and PSTv‐37 of the stripe rust pathogen. Castella exhibited excellent adult‐plant resistance to the pathogen in multiyear trials. Castella is resistant to toxic levels of aluminum and to the biotype of Hessian fly (Mayetiola destructor Say) that is prevalent in the PNW. Across 72 environments, Castella exhibited competitive grain yields compared with existing club and soft white cultivars and higher grain volume weight than the club wheat check ‘Bruehl’. Castella has maintained a falling number above 300 s more frequently than Bruehl and the club wheat ‘Pritchett’ in multiple testing years. Castella has excellent milling and baking properties including superior sponge cake volume and will increase the quality of the club wheat crop in the PNW.

Impact of a Dietary Wheat Intervention on the Gut Microbiota of Adult Humans

ObjectivesDiet is a key factor shaping the gut bacterial community of humans. Consumption of whole grain increases the diversity of the gut microbiota as well as beneficial microbes and their metabolites. However, previous research has not investigated the effect of different wheat types on the gut microbiome. MethodsIn this study, a sample of 28 adults consumed 100g per day of two different types of Michigan-grown whole grain wheat in the form of crackers made with flour of whole grain soft white wheat or whole grain soft red wheat. The study took place over a four-week period, each week representing a different treatment (A, B, C, and D). In weeks B and D participants consumed crackers made from white and red wheat, respectively. In weeks A and C, participants consumed crackers made from refined soft white wheat flour (washout). At the end of each 7-day period, participants submitted fecal samples for microbiota analysis as well as fiber and dietary questionnaires to assess their dietary intake. ResultsThe average daily fiber intake was 21.1g ± 13.8 g per day with a maximum fiber intake of 102.3 g and a minimum fiber intake of 6.7g. The average dietary diversity score in week A was 6.5, week B was 5.9, week C was 6.5, and week D was 5.6. The fecal bacterial communities did not differ in alpha diversity across time points. Bifidobacterium changed significantly throughout the treatment period. Community structure was similar across timepoints. However, four participants displayed a change in enterotype during the study period. A subset of six responders exhibited an increase in alpha diversity in test weeks (B and D). ConclusionsThe present study illustrated that these whole grain wheat treatments may not affect the composition of the gut microbiota in all adult humans, but a subset of participants did respond to the wheat treatment. The subset of responders suggests that baseline microbiota or background diet may influence changes in gut microbiota in response to whole grain wheat treatment. A larger sample size and increased treatment dose or treatment time period could further elucidate these relationships. Funding SourcesMichigan Soft White Wheat Endowment and Michigan State University AgBioResearch.

Association mapping of sponge cake volume in U.S. Pacific Northwest elite soft white wheat (Triticum aestivum L.)

Sponge cake quality is an essential end-use trait for U.S. Pacific Northwest (PNW) soft white (SW) wheat, primarily measured by the volume of a cake. The baking of each cake is relatively expensive, labor intensive, and requires a substantial amount of flour. As a result, sponge cake baking is conducted in later generations on a limited number of breeding lines. Insight into the genetic architecture of sponge cake volume would help provide an alternative to cake baking. Here we describe the analysis of 387 wheat genotypes spanning 27 crop years with a total of 685 environments for sponge cake volume. Genotyping by sequencing was used to generate molecular markers in wheat representing elite germplasm of the PNW. A genome wide association study was conducted to discover marker trait associations, while accounting for population structure and kinship. A total of six significant marker trait associations were identified on chromosomes 1AB, 2A, 3BD, 4A, and 6A. Collectively these marker trait associations explained 29.9% (ranging from 0.3 to 14.2%) of the sponge cake volume variation. Previous research detected associations with agronomic, grain, flour, milling and baking traits on each of these chromosomes, however, none for sponge cake volume. This study serves as a foundation experiment by providing insights into the genetic architecture of sponge cake volume in a historical dataset.

Sponge cake baking quality—An 18‐year retrospective

AbstractBackground and objectivesSponge cake quality is an essential end‐use trait for U.S. Pacific Northwest (PNW) soft white (SW) wheat. This study examined sponge cake volume of SW winter wheat germplasm from 48 balanced datasets spanning 18 years.FindingsHalf of the datasets returned significant whole model and variety ANOVA F‐values, compared to 35 with significant whole model and environment F‐values, indicating that environment was in general the greater source of variation. Low (mean 3.1%) coefficients of variation suggested that nonsignificant variety F‐values were due to no substantive genetic variation (as opposed to high error variance). Datasets with only two environments rarely returned significant whole model F‐values, and never significant genotype F‐values, whereas 93% of datasets with ≥5 environments had significant ANOVA models. Nevertheless, significant models did not always delineate genotypes. Infrequently were significant differences detected among the commercial varieties.ConclusionsIn terms of sponge cake volume, PNW soft white winter wheat varieties, especially club wheats varieties, are genetically similar and consistent. ANOVA indicated that varieties need to be grown in ≥5 environments to detect small genotype differences.Significance and noveltySponge cake quality has remained remarkably consistent among commercial soft white winter wheat varieties over 18 years of breeding and selection. The results indicate this consistency may be due to effective testing and selection, a narrow genetic germplasm base, or a combination thereof.