SDS Sedimentation Volume Research Articles

Assessing the Impact of Arabinoxylans on Dough Mixing Properties and Noodle-Making Performance through Xylanase Treatment.

This study examined the impact of xylanases, focusing on the hydrolysis of water-extractable (WE-AX) and water-unextractable arabinoxylans (WU-AX) and on the quality and noodle-making performance of flours with varying gluten strengths. Flours categorized as strong (S), medium (M), and weak (W) were treated with two xylanases (WE and WU) at concentrations ranging from 0.01% to 0.2%. Parameters such as solvent retention capacity (SRC), SDS sedimentation volume, dough mixing properties, and noodle characteristics were measured. The SRC revealed that flour S had the highest water-holding capacity, gluten strength, and arabinoxylan content. Xylanase treatment reduced water SRC values in flour S and increased the SDS sedimentation volume, with a greater effect from xylanase WU, indicating the potential enhancement of gluten strength. The impact of xylanases was pronounced at higher enzyme concentrations, with differences in dough mixing properties, resistance, and extensibility of fresh noodles, producing softer and stretchable noodles. Cooked noodles made from flours treated with xylanase were softer and had decreased firmness and chewiness, especially those made from flours S and M. This study concludes that WE-AX and WU-AX influence noodle texture; therefore, controlling their degradation with xylanases can produce noodles with varied textures, depending on the gluten strength of the flour.

On-farm assessment of yield and quality traits in durum wheat.

Durum wheat is key source of calories and nutrients for many regions of the world. Demand for it is predicted to increase. Further efforts are therefore needed to develop new cultivars adapted to different future scenarios. Developing a novel cultivar takes, on average, 10 years and advanced lines are tested during the process, in general, under standardized conditions. Although evaluating candidate genotypes for commercial release under different on-farm conditions is a strategy that is strongly recommended, its application for durum wheat and particularly for quality traits has been limited. This study evaluated the grain yield and quality performance of eight different genotypes across five contrasting farmers' fields over two seasons. Combining different analysis strategies, the most outstanding and stable genotypes were identified. The analyses revealed that some traits were mainly explained by the genotype effect (thousand kernel weight, flour sodium dodecyl sulfate sedimentation volume, and flour yellowness), others by the management practices (yield and grain protein content), and others (test weight) by the year effect. In general, yield showed the highest range of variation across genotypes, management practices, and years and test weight the narrowest range. Flour yellowness was the most stable trait across management conditions, while yield-related traits were the most unstable. We also determined the most representative and discriminative field conditions, which is a beneficial strategy when breeders are constrained in their ability to develop multi-environment experiments. We concluded that assessing genotypes in different farming systems is a valid and complementary strategy for on-station trials for determining the performance of future commercial cultivars in heterogeneous environments to improve the breeding process and resources.

Estimating technological quality parameters of bread wheat using sensor-based Normalized Difference Vegetation Index

This multi-environment study aimed to investigate the usability of the sensor-based Normalized Difference Vegetation Index (NDVI) for estimating bread wheat technological quality properties. The relationships between the technological quality properties and NDVI Zadoks (ZD) 31 stage readings were evaluated by grouping the trials as low and high-yielding environments (LYE and HYE). According to the results, the quality parameters and grain yield were higher in the HYE compared to the LYE group. Generally, the increase in the grain protein content (GPC), macro SDS sedimentation (MSDS) volume, and GlutoPeak aggregation energy (AGGEN) value differences became evident after 80 kg ha−1 nitrogen dose in the LYE, while, significant effects were observed after 40 kg ha−1 dose in the HYE. The equations developed in this study can be used for the estimation of GPC, and technological quality properties in the NDVI ZD31 stage. The R2s of the regression equations developed for the actual and predicted technological quality parameters of bread wheat were 0.216 for GPC, 0.295 for MSDS, and 0.226 for AGGEN values (p < 0.01; n = 240). As a result of this study, the reading value of 0.758 was found as a critical NDVI ZD31 threshold for the recommendation of nitrogen to obtain high technological quality.

글루텐 강도가 다른 미국산 연질밀가루의 건면 제조 적성 비교

Purpose: The present study compared the dry noodle-making performance of US soft wheat flours with different gluten strength. Methods: Three flours (weak, medium, and strong gluten strength - W, M, and S, respectively) milled from US Soft Red Winter (SRW) wheat cultivars and a commercial all-purpose flour (control) were analyzed for their physicochemical properties including pasting property, SDS sedimentation volume, solvent retention capacity (SRC), and dry noodle-making performance. Results: The three soft wheat flours were significantly different in SDS sedimentation volume, lactic acid SRC, and gluten performance index, whereas the all-purpose flour had similar SDS sedimentation value and lactic acid SRC to S flour, and gluten performance index similar to the M flour. The peak viscosity of pasting, final viscosity, and peak time of the all-purpose flour were within the range of soft flours. The resistance (R) and extensibility (E) of the fresh noodles were in the order of W<M<S flour. The R and E of the all-purpose flour were greater than all three soft wheat flours, but the R/E of the flour was similar to the S flour. The firmness and chewiness measured after boiling the dry noodles made with the S soft wheat flour were higher or similar, compared to those made with the all-purpose flour. Conclusions: Soft wheat flour with high gluten strength was suitable for making dry white-salted noodles. The SDS sedimentation volume, lactic acid SRC, and gluten performance index of the soft wheat flours could be useful indicators for selecting a soft wheat flour suitable for dry white-salted noodle production.

Effects of Wheat Bran Micronization on the Quality of Reconstituted Whole-Wheat Flour and Its Cooked Noodles

The particle size of wheat bran plays an important role in the quality of reconstituted whole-wheat flour and its products. The effects of wheat bran particle size on the quality of reconstituted whole-wheat flour and its cooked noodles were analyzed; the mean particle size (D50) of wheat bran ranged from 26.05 to 46.08 μm. Results show that the decreases in D50 of wheat bran induced the changes in the quality of whole-wheat flour and its noodles. Specifically, the damaged starch content, water absorption, and the solvent retention capacity of sodium carbonate and sucrose of whole-wheat flour increased at various degrees, while pasting viscosity decreased, and the gluten index and SDS-sedimentation volume increased first and then decreased. The cooking yield, cooking loss, and break rate of fresh noodles decreased first and reached a trough at D50 of 26.05 μm, and then increased. The adhesiveness of cooked noodles increased, the score of smoothness, taste, appearance, and color increased to a stable value, but the hardness, springiness, cohesiveness, resilience, firmness score, and elasticity score increased first and then decreased. These turning points of changing trends of indexes mostly occurred when the D50 of wheat bran was 26.51 μm. In conclusion, whole-wheat noodles with wheat bran of D50 of 26.51 μm addition exhibit better cooking, textural, and sensory properties than those with smaller or larger wheat bran. Excessive crushing of wheat bran not only costs highly in terms of energy, but also has a negative impact on the quality of the noodles.

알러지 저감밀 오프리 밀가루의 품질 특성과 제빵 및 제면 적성

Purpose: This study aimed to explore the quality characteristics and bread-making and noodle-making properties of low allergy wheat (‘O-free’) flour. Methods: ‘O-free’ flour and three commercial wheat flours (high-H, medium-M, low-L gluten strength) were used. Solvent retention capacity (SRC), sodium dodecyl sulfate (SDS)-sedimentation volume, pasting and gelatinization properties using rapid visco analyzer and differential scanning calorimetry, and dough mixing property using a mixograph of the flour samples were determined. In addition, their bread- and noodle-making performance was evaluated. Results: The SRC values in all four solvents and the SDS-sedimentation volume of ‘O-free’ flour were lower than those of H and M flour and higher than those of L flour. The pasting and gelatinization properties of ‘O-free’ flour starch were similar to those of the other flour samples. The dough mixing property and bread-making performance of the ‘O-free’ flour were inferior to the H and M flour but superior to the L flour. On the other hand, the noodle-making performance of the ‘O-free’ flour was inferior to all three flours. Conclusions: Overall, it was confirmed that ‘O-free’ flour, which lacks omega-gliadin, has inferior gluten protein quality and processing performance compared to H or M flours that are mainly used for making bread and noodles. Performance improvement was necessary by controlling other basic ingredients and processing conditions.

Identification and Validation of Stable Quantitative Trait Loci for SDS-Sedimentation Volume in Common Wheat (Triticum aestivum L.).

Sodium dodecyl sulfate-sedimentation volume is an important index to evaluate the gluten strength of common wheat and is closely related to baking quality. In this study, a total of 15 quantitative trait locus (QTL) for sodium dodecyl sulfate (SDS)-sedimentation volume (SSV) were identified by using a high-density genetic map including 2,474 single-nucleotide polymorphism (SNP) markers, which was constructed with a doubled haploid (DH) population derived from the cross between Non-gda3753 (ND3753) and Liangxing99 (LX99). Importantly, four environmentally stable QTLs were detected on chromosomes 1A, 2D, and 5D, respectively. Among them, the one with the largest effect was identified on chromosome 1A (designated as QSsv.cau-1A.1) explaining up to 39.67% of the phenotypic variance. Subsequently, QSsv.cau-1A.1 was dissected into two QTLs named as QSsv.cau-1A.1.1 and QSsv.cau-1A.1.2 by saturating the genetic linkage map of the chromosome 1A. Interestedly, favorable alleles of these two loci were from different parents. Due to the favorable allele of QSsv.cau-1A.1.1 was from the high-value parents ND3753 and revealed higher genetic effect, which explained 25.07% of the phenotypic variation, mapping of this locus was conducted by using BC3F1 and BC3F2 populations. By comparing the CS reference sequence, the physical interval of QSsv.cau-1A.1.1 was delimited into 14.9 Mb, with 89 putative high-confidence annotated genes. SSVs of different recombinants between QSsv.cau-1A.1.1 and QSsv.cau-1A.1 detected from DH and BC3F2 populations showed that these two loci had an obvious additive effect, of which the combination of two favorable loci had the high SSV, whereas recombinants with unfavorable loci had the lowest. These results provide further insight into the genetic basis of SSV and QSsv.cau-1A.1.1 will be an ideal target for positional cloning and wheat breeding programs.

Effects of the functional Gpc‐B1 allele on soft durum wheat grain, milling, flour, dough, and breadmaking quality

AbstractBackground and objectivesUtilization of durum wheat (Triticum turgidum subsp. durum) can be enhanced by increasing grain and flour protein content. One strategy to increase protein content is by introducing the functional Gpc‐B1 allele from wild emmer (Triticum turgidum subsp. dicoccoides).FindingsIntroduction of the functional Gpc‐B1 allele into soft kernel durum increased grain and flour protein by 17 g/kg, increased dough strength as evidenced by SDS sedimentation volume and Mixograph dough mixing parameters, and increased straight‐dough pan bread volume. When grown under arid conditions, high protein (151 g/kg) samples had decreased loaf volumes indicative of inelastic doughs. The functional Gpc‐B1 allele was associated with decreased test weight, a small increase in SKCS hardness, and a modest increase in flour ash; otherwise, milling performance was not affected.ConclusionsIntrogression of the Gpc‐B1 functional allele from dicoccoides into durum wheat can improve dough strength and breadmaking quality. The effect tends to be consistent over environments but overall, Gpc‐B1 made only a modest improvement in durum wheat breadmaking quality. Further studies with concomitant selection at other loci are needed to see the effects of Gpc‐B1 among elite germplasm.Significance and noveltyDurum wheat production and consumption will increase as bread quality improves. The functional Gpc‐B1 allele contributed to improved breadmaking quality. The present report is the first to examine the effect of this allele on breadmaking in durum wheat.

Grain quality indices in common wheat lines with introgressions of chromosome 1U from Aegilops biuncialis Vis.

Aim. The aim of this study was to analyze grain quality indices in winter common wheat lines with introgressions of chromosome 1U from Aegilops biuncialis Vis. marked by storage protein loci. Methods. Acid polyacrylamide gel electrophoresis and SDS-electrophoresis of storage proteins were performed to identify introgressions. Grain quality indices (SDS sedimentation volume and grain protein content) were analyzed in lines with introgressed chromosome 1U or its arm 1UL, as well as in the cultivars Panna and Bezostaya 1. Results. SDS-sedimentation volume in the cultivars and lines depended on year’s conditions. The studying of the lines during two years has demonstrated that the presence of the allele at the high molecular weight glutenin subunit locus Glu-U1 from Ae. biuncialis was associated with a high volume of SDS-sedimentation SDS30 (higher than that in the cultivar Bezostaya 1). The introgressive lines show high grain protein content. Conclusions. The effect of the allele at the high molecular weight glutenin subunit locus Glu-U1 from Ae. biuncialis on SDS-sedimentation value is similar to that of the high-quality allele Glu-B1al. The lines with the introgressed allele at Glu-U1 from Ae. biuncialis are valuable initial material for breeding for quality.Keywords: Triticum aestivum, Aegilops biuncialis, high molecular weight glutenin subunits, SDS-sedimentation, protein content.

Effects of Glu‐D1 gene introgressions on soft white spring durum wheat (Triticum turgidum ssp. durum) quality

AbstractBackground and objectivesUtilization of durum wheat (Triticum turgidum ssp. durum) is limited by its weak gluten and poor bread‐making quality. One strategy to improve gluten strength and bread‐making quality is by introducing the Glu‐D1 alleles from bread wheat.FindingsIntroduction of Glu‐D1 alleles Glu‐D1a and Glu‐D1d, corresponding to the High Molecular Weight Glutenin subunits Dx2 + Dy12 and Dx5 + Dy10, respectively, increased dough strength as evidenced by SDS sedimentation volume, Lactic acid Solvent Retention Capacity, and Mixograph dough mixing parameters. The Glu‐D1d Dx5 + Dy10 allele was “stronger” than the Glu‐D1a Dx2 + Dy12 allele. However, whereas Dx2 + Dy12 improved straight‐dough pan bread volume, Dx5 + Dy10 did not. This latter result was ascribed to the overly strong, inextensible gluten contributed by the Glu‐D1d Dx5 + Dy10 allele.ConclusionsWhereas both Glu‐D1 alleles increased dough strength, Dx2 + Dy12 improved bread loaf volume but lines with Dx5 + Dy10 produced doughs that were too strong to realize an increase in loaf volume. The results confirm the notion that large bread loaf volume is achieved with a balance of dough extensibility and elasticity.Significance and noveltyDurum wheat production and consumption will increase as bread quality improves. The Glu‐D1 high molecular weight glutenin proteins will likely play a role in improving bread‐making ability. The two major Glu‐D1 alleles are accessible via durum wheat translocation lines.

The effect of glutenins on grain quality as one of the complex polygenic traits in the genus Triticum (a review)

Evaluation of plant breeding material, based on protein markers, gives an opportunity to perform rapid and reliable selection and control the transfer of desired traits from parents to their progeny. A search for new and stable protein markers is needed to identify genotypes with high grain quality. Such storage proteins in wheat as glutenins have been studied profoundly enough. Full characterization of individual protein fractions and components can be found in many scienti fic publications, while studying genetic patterns of protein accumulation in the grain of different wheat cultivars and using high-molecular-weight (HMW) and lowmolecular-weight (LMW) glutenin subunits (GS) for genotype identi fication remain high in the research agenda. This is a comprehensive review of scienti fic publications about the structure and molecular organization of glutenins and a comparative analysis of 22 research papers about the degree of their effect on grain quality indicators: SDS-sedimentation volume (ml), grain/ flour protein content (%; 14% m.b.; 12,5% m.b.), mixing time (min), mixing tolerance (min; mm), bread loaf volume (cm3; ml), dough strength (10 -4 J), and P/L ratio. As a result of reviewing, the best alleles (subunits) of glutenin were identi fied, namely: Glu-A1а, Glu-B1(h, f, b), Glu-D1d, Glu-A3d, and Glu-B3d.

The effect of mutations in the alleles Gli-B1b and Gli-B1l on grain quality indices of common wheat

Aim. The aim of this study was to analyze quality indices in mutants at gliadin loci developed on the basis of the common wheat cultivar Bezostaya 1. Methods. Acid polyacrylamide gel electrophoresis and SDS-electrophoresis of storage proteins were performed to check mutations. Grain quality indices (SDS sedimentation volume, grain hardness, seed plumpness, and grain protein content) were analyzed: Results. Both mutants at Gli-R1 with the intensified secalin component and with the changed mobility of the secalin component showed lower grain hardness in comparison with the respective non-mutant lines. The mutation of the allele Gli-B1b causing the absence of synthesis of the g-gliadin and the minor w-gliadin resulted in the decrease in grain hardness and in the increase in the SDS-sedimentation volume. Seeds of the Gli-B1b mutant with the absence of synthesis of the major w-gliadin were less plump and showed higher protein content than in the non-mutant line. Conclusions. The effects of mutations of the allele Gli-B1b associated with the absence of certain gliadin components and Gli-R1 mutations on grain quality indices were revealed.&#x0D; Keywords: Triticum aestivum, gliadins, secalins, SDS-sedimentation, grain hardness.

What should organic farmers grow: heritage or modern spring wheat cultivars?

To achieve a complete organic value chain, we need organic seed from cultivars adapted to organic growing. A separate breeding for organic growing is difficult to achieve in small markets. Many breeding goals are equal for organic and conventional cereals, and cultivars failing to qualify as a commercial variety for conventional growing may possibly perform well in organic growing, with different regimes of fertilisation and plant protection. A field trial was conducted over 2 years to compare 25 cultivars of spring wheat, ranging from one land race and some old varieties released between 1940 and 1967, to modern market varieties and breeding lines. Grain yield, agronomic characteristics and grain and flour quality, including mineral content, were recorded. The performance of the 20 most interesting cultivars in artisan bread baking was measured, as were sensory attributes in sourdough bread from six cultivars. Modern varieties and breeding lines gave higher yields and had larger kernels, better grain filling, higher falling numbers and higher SDS-sedimentation volumes compared with old cultivars. The old cultivars, on average, had higher concentrations of minerals, although the growing site had a strong effect on mineral concentrations. Bread from modern cultivars performed best in a baking test. Several sensory attributes such as juiciness, chew resistance, firmness, acid taste and vinegar odour varied significantly between the six tested cultivars. Land races and old varieties have an important cultural value, and many consumers are willing to pay a premium price for such products. This will be required since yield levels are often considerably lower, especially with humid weather conditions at harvest.

Reducing the Immunogenic Potential of Wheat Flour: Silencing of Alpha Gliadin Genes in a U.S. Wheat Cultivar.

The alpha gliadins are a group of more than 20 proteins with very similar sequences that comprise about 15%–20% of the total flour protein and contribute to the functional properties of wheat flour dough. Some alpha gliadins also contain immunodominant epitopes that trigger celiac disease, a chronic autoimmune disease that affects approximately 1% of the worldwide population. In an attempt to reduce the immunogenic potential of wheat flour from the U.S. spring wheat cultivar Butte 86, RNA interference was used to silence a subset of alpha gliadin genes encoding proteins containing celiac disease epitopes. Two of the resulting transgenic lines were analyzed in detail by quantitative two-dimensional gel electrophoresis combined with tandem mass spectrometry. Although the RNA interference construct was designed to target only some alpha gliadin genes, all alpha gliadins were effectively silenced in the transgenic plants. In addition, some off-target silencing of high molecular weight glutenin subunits was detected in both transgenic lines. Compensatory effects were not observed within other gluten protein classes. Reactivities of IgG and IgA antibodies from a cohort of patients with celiac disease toward proteins from the transgenic lines were reduced significantly relative to the nontransgenic line. Both mixing properties and SDS sedimentation volumes suggested a decrease in dough strength in the transgenic lines when compared to the control. The data suggest that it will be difficult to selectively silence specific genes within families as complex as the wheat alpha gliadins. Nonetheless, it may be possible to reduce the immunogenic potential of the flour and still retain many of the functional properties essential for the utilization of wheat.

Re-evolution of Durum Wheat by Introducing the Hardness and Glu-D1 Loci

Durum wheat is an important crop worldwide. In many areas, durum wheat appears to have competitive yield and biotic and abiotic advantages over bread wheat. What limits durum production? In one respect, the comparatively more limited processing and food functionality. Two traits directly relate to these limitations: kernel texture (hardness) and gluten strength. We have addressed both using ph1b-mediated translocations from bread wheat. For kernel texture, ca. 28 Mbp of chromosome 5DS replaced about 20 Mbp of 5BS. SKCS hardness was reduced from ca. 80 to 20 as the puroindolines were expressed and softened the endosperm. Break flour yields increased from 17% to >40%. Straight-grade flour had low starch damage (2%), and a mean particle size of 75 µm. Crosses with CIMMYT durum lines all produced soft kernel progeny and a high degree of genetic variance for milling and baking quality. Solvent Retention Capacities (SRC) and cookie diameters were similar to soft white hexaploid wheat, showing that soft durum can be considered a “tetraploid soft white spring wheat”. Regarding gluten strength, CIMMYT durums contributed a high genetic variance, with the “best” progeny exhibiting SDS sedimentation volume, SRC Lactic Acid and Mixograph characteristics that were similar to medium-gluten strength U.S. hard red winter. The best loaf volume among these progeny was 846 cm3 at ca. 12.8% flour protein. To further address the issue of gluten strength, Soft Svevo was crossed with durum lines possessing Dx2+Dy12 and Dx5+Dy10. Bread baking showed that Dx5+Dy10 was overly strong, whereas Dx2+Dy12 significantly improved bread loaf volume. The best progeny produced a loaf volume of 1010 cm3 at 12.1% protein. As a comparison, the long-term in-house regression for loaf volume-flour protein for hard red ‘bread’ wheats is 926 cm3 at 12.1% protein. Obviously, from these results, excellent bread making potential has been achieved.

Nitrogen management, cultivars and growing environments on wheat grain quality

ABSTRACT The aim of this study was to evaluate the influence of nitrogen (N) fertilization, environment and cultivars on the protein concentration, sodium dodecyl sulfate sedimentation test (SDSS) volume and falling number in wheat. The experimental design was a randomized blocks in split plot scheme with four repetions. Four wheat genotypes were evaluated under six N managements in four enviroment (subplots). The wheat genotypes evaluated were IPR Catuara TM, BRS Gaivota, Quartzo and CD 120. Protein concentration, SDS sedimentation test, falling number and grain yield were evaluated. Combined analysis of variance for the four environment was performed and means were compared by Tukey test at p ≤ 0.05. The environmental effect is greater than the genotype and N effects on protein concentration. The increase in protein concentration reduces grain yield of the cultivars tested. SDSS and falling number in wheat are influenced by the interaction between cultivar and environment and also by the N management. The protein concentration of grain has low influence on SDS sedimentation volume, so the topdressing N management has less accentuated effect on this response variable. The falling number does not vary among cultivars when the environment is suitable to pre-harvest sprouting. The use of topdressing N influences the falling number in wheat.

Influence of low soil nitrogen and phosphorus on gluten polymeric and monomeric protein distribution in two high quality spring wheat cultivars

The effect of low levels of nitrogen, phosphorus and a combination of the two on the distribution of polymeric and monomeric proteins in two high quality spring bread wheat cultivars was investigated for two consecutive seasons. Size exclusion-high performance liquid chromatography (SE-HPLC) was used to determine the quantity and relationships of monomeric and polymeric proteins, and their relationship with flour protein content (FPC) and SDS sedimentation volume (SDSS). The low nitrogen and combined low nitrogen and low phosphorus treatments had a much larger effect on the protein fractions than the low phosphorus treatment alone. The SDS-soluble large monomeric protein fraction and the percentage SDS-insoluble monomeric proteins, were significantly increased under low nitrogen and a combination of low nitrogen and low phosphorus treatments. The percentage SDS-insoluble large and total polymeric proteins was significantly reduced under low nitrogen and a combination of low nitrogen and phosphorus treatments. The SDS-soluble and -insoluble small polymeric proteins were significantly increased under both low nitrogen and a combination of low nitrogen and low phosphorus treatments. The low nitrogen treatment consistently caused the lowest FPC and SDSS values. Under low nitrogen conditions, there was a significant positive correlation between the SDS-soluble gliadins and SDSS, and FPC.

Evaluation of Fusarium head blight resistance genes Fhb1, Fhb2, and Fhb5 introgressed into elite Canadian hard red spring wheats: effect on agronomic and end-use quality traits and implications for breeding

Utilizing exotic sources of genes (from lines originating in China and Brazil) to develop resistance to Fusarium head blight (FHB) in common wheat is an established practice in North America due to lack of comparable resistance (smaller phenotypic effect) in local germplasm and/or associated markers for ease of selection. This study evaluated the effects of three major Sumai 3-derived FHB resistance genes Fhb1, Fhb2, and Fhb5, and other minor alleles inherited during crossing, on agronomic and end-use quality traits in hard red spring wheats from Canada. The BC3 derived near-isogenic lines in CDC Go (n = 38) and CDC Alsask (n = 32) backgrounds carrying all possible combinations of these three major genes were tested in six site-years. Among agronomic traits, introgressions resulted in lower thousand kernel weight and increased plant height with Fhb5. Among end-use quality traits, SDS-sedimentation volume, and grain protein content were affected. In addition to Fhb1, Fhb2, and Fhb5, we identified 10 loci in CDC Alsask NILs and 9 in CDC Go NILs that affected the traits measured. We found that none of these additional loci were common in both populations, indicating the presence of many alleles in exotic sources that can result in linkage drag. Linkage drag is largely dependent on the genetic background and the proportion of resistance alleles. Therefore, we observed more adverse effects in CDC Alsask NILs than in CDC Go. Improvements in FHB resistance can still be made by introgressing these major genes using marker-assisted selection and selecting rare segregants with improved agronomic and end-use quality.

Molecular characterization and marker development for high molecular weight glutenin subunit 1Dy12** from Yunnan hulled wheat

High molecular weight glutenin subunits (HMW-GSs) play an important role in affecting dough viscoelasticity and extensibility. In this work, the novel HMW-GS gene 1Dy12** in Yunnan hulled wheat was cloned and characterized, and the molecular marker for identifying this gene was developed. SDS-PAGE analysis indicated that the mobility of 1Dy12** was the same as that of 1Dy12. The coding sequence of 1Dy12** was 1953 bp, which was 33 bp less than that of 1Dy12. 1Dy12** possessed 649 amino acid residues and showed a similar molecular structure to the published y-type subunit. It possessed four domains: a signal peptide, a conservative N-terminal domain, a large repetitive domain, and a conservative C-terminal domain. Eight cysteine residues were present in 1Dy12**, which was one more than the conserved number of cysteine residues in the y-type subunit. In vitro SDS-sedimentation tests demonstrated that 1Dy12** could bring higher SDS-sedimentation volumes than those of 1Dy10 or 1Dy12. A set of functional markers for the 1Dy12** gene was developed and validated on 36 bread wheat varieties with different Glu-1 alleles and 48 recombinant inbred lines derived by Yunnan hulled wheat and Yanzhan 1. The markers could effectively distinguish 1Dy12** from other HMW-GS genes and, thus, provide a useful tool for marker-assisted selection in wheat quality improvement programs.

Mapping Some Seed Quality Traits in Bread Wheat (Triticum aestivum L.) by Association Mapping Using SSR Markers

Introduction: Quality characteristics including grain protein content, gluten, falling number, and SDS sedimentation volume are important contributors to the grain yield and quality of the wheat. To identify the markers associated with such traits, this study run in two separated experiments: under-field and in laboratory. Materials and Methods: One hundred wheat genotypes were evaluated in an alpha lattice design with two replications. Association mapping using Structure and Tassel software was carried out using 102 SSR markers: 66 unlinked and 36 quantitative trait loci (QTL)-linked SSR markers. Correction for population structure was performed using genome-wide SSR markers so that genotypes were divided into six subpopulations. Results: Thoroughly, 34 SSR markers linked with the above-mentioned traits were identified, twelve of them being QTL-linked markers. These markers were already mapped on the wheat chromosomes in previous studies containing known QTLs controlling kernel traits of the wheat. Our results confirmed 5, 3, 2, and 2 QTLs respectively for the grain protein, gluten, falling number, and SDS sedimentation volume which were previously tagged on the wheat chromosomes. Additionally, 3 QTLs were identified for the grain protein on the chromosomes 2A, 5A, 5D, and 7B. Whereas, 6 QTLs for gluten were detected on chromosomes 1A, 2D, 5A, 5B, 6B, and 7B; four QTLs were located on the chromosomes 2D, 5A, 5B, 5D, and 7D for falling number; and finally nine QTLs were found for SDS sedimentation volume on the chromosomes 1A, 1B, 2B, 3A, 3B, 4B, 6A, 6B, 7A, and 7B. Conclusions: The results of this study indicated that association mapping is a useful method for detecting and complementing QTL information; thus, this information can be used for further wheat improvement based on a molecular marker.