Glutenin Subunits Research Articles

Detection of Sensitization Profiles with Cellular In Vitro Tests in Wheat Allergy Dependent on Augmentation Factors (WALDA).

Wheat allergy dependent on augmentation factors (WALDA) is the most common gluten allergy in adults. IgE-mediated sensitizations are directed towards ω5-gliadin but also to other wheat allergens. The value of the different in vitro cellular tests, namely the basophil activation test (BAT) and the active (aBHRA) and passive basophil histamine-release assays (pBHRA), in the detection of sensitization profiles beyond ω5-gliadin has not been compared. Therefore, 13 patients with challenge-confirmed, ω5-gliadin-positive WALDA and 11 healthy controls were enrolled. Specific IgE (sIgE), skin prick tests, BATs, aBHRA, and pBHRA were performed with allergen test solutions derived from wheat and other cereals, and results were analyzed and compared. This study reveals a distinct and highly individual reactivity of ω5-gliadin-positive WALDA patients to a range of wheat allergens beyond ω5-gliadin in cellular in vitro tests and SPT. In the BAT, for all tested allergens (gluten, high-molecular-weight glutenin subunits, α-amylase/trypsin inhibitors (ATIs), alcohol-free wheat beer, hydrolyzed wheat proteins (HWPs), rye gluten and secalins), basophil activation in patients was significantly higher than in controls (p = 0.004-p < 0.001). Similarly, significant histamine release was detected in the aBHRA for all test substances, exceeding the cut-off of 10 ng/mL in all tested allergens in 50% of patients. The dependency of tests on sIgE levels against ω5-gliadin differed; in the pBHRA, histamine release to any test substances could only be detected in patients with sIgE against ω5-gliadin ≥ 7.7 kU/L, whereas aBHRA also showed high reactivity in less sensitized patients. In most patients, reactivity to HWPs, ATIs, and rye allergens was observed. Additionally, alcohol-free wheat beer was first described as a promising test substance in ω5-gliadin-positive WALDA. Thus, BAT and aBHRA are valuable tools for the identification of sensitization profiles in WALDA.

Glu-A3b allelinin rekombinant kendilenmiş hat popülasyonunda ekmeklik buğdayın gluten kalitesi üzerinde önemli bir etkisi vardır

In this study, a total of 147 wheat lines with variying low molecular weight glutenin subunits (LMW-GS), obtained by crossing Tosunbey and Tahirova2000 bread wheats, were included. Milling, protein, dough-mixing properties of the genotypes were measured and their relations with LMW-GS were investigated in eight different environments. As the LMW-GS of the parents were quite different; milling, protein and dough-mixing properties of the lines were significantly influenced. In this regard, presence of rye translocation (Glu-B3j) reduced flour yield and increased damaged starch and protein contents. In terms of protein quality, Glu-A3b+Glu-B3b allellic combinations were better than GluA3b+Glu-B3j or Glu-A3e +Glu-B3j allellic combinations. It was observed that negative effects of rye translocation could be minimized by selecting proper Glu-3 alleles, such as Glu-A3b instead of Glu-A3e. LMW-GS combinations of the lines influenced mixolab mixing and thermorheological properties. In this respect, the lines with Glu-A3b or Glu-B3b allelles showed increased mixing time and stability as compared to the lines with Glu-A3e or Glu-B3j allelles. The effect of LMW-GS alleles on gluten quality and dough strength was statistically bb &gt; eb &gt; bj &gt; ej. In terms of myxolab stability value related to bread volume; 1 = 2*, 7 + 9 &gt; 17 +18, b &gt; e and b &gt; j; in terms of mixing time; 1 &gt; 2*, 7 + 9 &lt; 17 +18, b &gt; e and b &gt; j. As a result, the Glu-A3b allele can be used to increase gluten quality, and the Glu-B3j allele can be used to increase protein content. Proper allellic combinations of LMW-GS in wheat can be developed for a given bakery product.

HMW-GSs 1Dx3+1Dy12 contribute to a suitable wheat gluten strength that confers superior Chinese steamed bread quality.

The aim of this study was to clarify the effects of the high-molecular-weight glutenin subunits (HMW-GSs) 1Dx3+1Dy12 (3+12) and 1Dx4+1Dy12 (4+12) at the Glu-D1 locus on gluten and Chinese steamed bread (CSB) quality. The grain protein content and composition, gluten content and gluten index, farinograph properties, and CSB quality were investigated using four wheat near-isogenic lines (NILs) carrying HMW-GSs 1Dx2+1Dy12 (2+12), 3+12, 4+12 and 1Dx5+1Dy10 (5+10), respectively. The unextractable polymeric protein (UPP) and glutenin macropolymer (GMP) content, gluten index, dough development time, stability time, and farinograph quality number of four NILs all ranked as 5+10>3+12>2+12/4+12, such as the gluten index ranked as 5+10(44.88%)>3+12(40.07%)>2+12(37.46%)/4+12(35.85%); however, their contributions to the quality of CSB were ranked as 3+12>5+10>2+12/4+12, such as the specific volume ranked as 3+12(2.64mL/g)>5+10(2.49mL/g)>2+12(2.36mL/g)/4+12(2.35mL/g), which indicated that a suitable gluten strength (3+12) was crucial to making high-quality CSB. In addition, subunits 4+12 had a similar quality performance to low-quality subunits 2+12. All these findings suggested that, except for the acknowledged high-quality subunits 5+10, the introduction of 3+12 at the Glu-D1 locus is an efficient way for quality improvement of gluten as well as CSB.

Effect of high-molecular-weight glutenin subunits silencing on dough aggregation characteristics

The qualities of wheat dough are influenced by the high-molecular-weight glutenin subunits (HMW-GS), a critical component of wheat gluten protein. However, it is still unknown how HMW-GS silencing affects the aggregation characteristics of dough. Two groups of near-isogenic wheat were used to study the effects of HMW-GS silencing on dough aggregation characteristics, dough texture characteristics, and dough microstructure. It was observed that the content of gliadin in LH-11 strain significantly increased compared to the wild-type (WT). Additionally, the amount of glutenin macropolymer and the glutenin/gliadin both decreased. The aggregation characteristics and rheological characteristics of the dough in LH-11 strain were significantly reduced, and the content of β-sheet in the dough was significantly reduced. The HMW-GS silencing resulted in a reduction in the aggregation of the gluten network in the dough, which related to the alteration of the secondary and microstructure of the gluten.

Causal Artificial Intelligence Models of Food Quality Data.

Causal Artificial Intelligence Models of Food Quality Data.

Effects of the 1RS.1BL wheat-rye translocationon kernel and bran content of bread wheat (Triticum aestivum L.)

In this study, the effects of rye translocation on some quality properties and mineral content of whole wheat kernel and bran were investigated.The plant material consisted of 147 recombinant inbred lines (RILs) and five control cultivars, including the parent. The genotypes were grown in Turkey at two different locations for two consecutive years. In the study, lines with and without rye translocation were determined by SDS-PAGE and PCR analysis, and the glutenin subunits of the lines at Glu-A1, Glu-B1, Glu-A3 and Glu-B3 loci were also analyzed. The protein, starch, fat, ash, dry matter, acid detergent insoluble fiber (ADF), neutral detergent insoluble fiber (NDF), potassium (K), phosphorus (P) and magnesium (Mg) contents of kernels and bran of the RILs were determined. Statistically significant differences were found between the genotypes in terms of all the examined characteristics except the amount of dry matter. The RILs carrying translocation 1RS.1BLhad a higher average ADF, NDF, protein content, ash content, K, Mg, and P contents of kernels, as well as a higher average ADF, NDF, ash, and K bran contents than the RILs without thetranslocation. The bran of the RILs without thetranslocationhad higher values in terms of fat, starch, and phosphorus content. The results indicate that wheat- rye translocation1RS.1BL has a significant effect on both whole wheat kernel and bran content, and can be used to enrich the content of wheat bran.

Effects of environmental temperature during maturation on protein characteristics in spring wheat (Triticum aestivum cv. Haruyokoi)

Wheat (Triticum aestivum cv. Haruyokoi) gluten proteins are important contributors to wheat flour quality. Numerous studies have examined the effects of heat stress on gluten proteins. We clarified the relationship between growth temperature and the characteristics of storage proteins in spring wheat grown under mild conditions (<30 °C). As the growth temperature increased, crude protein content also increased and the activity of protein disulfide isomerase (PDI), which is involved in the folding and transport of gluten proteins, decreased. The growth temperature also affected the amount of aggregated storage proteins, with an increase in sodium dodecyl sulfate (SDS)-insoluble proteins observed under high-temperature conditions. From these results, it was inferred that high growth temperatures caused an environment where nonspecific aggregation is likely to occur. The accumulation of specific proteins was also affected. The high-molecular-weight glutenin subunit (HMW-GS) Dx5 encoded by Glu-D1d allele, which has a marked impact on the viscoelastic properties of dough characteristics, showed high accumulation under high growth temperatures. These effects of growth temperature on storage proteins appear to affect the formation of glutenin macropolymer, which in turn affects the physical properties of the dough. As global warming continues, this study could provide helpful information for long-term predictions of wheat quality.

Effects of high-molecular-weight glutenin subunit on hard-steamed bread quality.

Steamed bread (SB) is a daily food in many countries in the world, but the relationship between HMW-GS and the quality of SB remain unclear. This study investigated the effects of 12 subunit combinations on the characteristics of SB, including volume, physical properties, and sensory evaluation, combined with the microstructure and dough rheological properties. The locus effect results showed, volume and physical properties of SB were Glu-D1>Glu-B1>Glu-A1, while sensory scores Glu-B1>Glu-D1>Glu-A1. According to individual subunit effects, subunit 1 at Glu-A1 locus, 7+8 and 7+9 subunits at Glu-B1 locus, and 2+10 and 5+12 subunits at Glu-D1 locus were significantly superior to other subunits in physical indices like volume, chewiness, glueyness, and sensory scores, and were less affected by moisture. The effect of subunits combination is mainly affected by subunits, and the combination of superior subunits tends to make SB quality better. The subunit combinations (1, 7+8, 5+12), (N, 7+9, 2+10) and (1, 7+9, 5+12) had better physical properties indexes, sensory scores, dense, uniform and delicate micro-pore structure, and smaller thickness wall. The results showed that protein content, wet gluten content and stability time were the main factors affecting the volume and physical properties of SB. The protein content, wet gluten content and stability time of flour in 7+8, 7+9, 2+10 and 5+12 subunits were higher. Therefore, the quality of SB containing these subunits was found better.

The Effect of High Molecular Weight Glutenin Subunit Encoded by Glu-B1k Allele on Bread-Making Quality of Near-Isogenic Lines of Bread Wheat

: In this study, the effect of the 22 glutenin subunit encoded by the Glu-B1k allele on the chromosome B on the quality of wheat was investigated. Nevzatbey and a genotype of Triticum aestivum L. subsp. sphaerococcum were used as parents and produced the near-isogenic lines (NILs) in the generation of BC4F3. Plant morphological traits and protein content, sedimentation volume, lactic acid solvent retention capacity (SRC), and glutenin swelling index (GSI) of the NILs were determined. The mean protein content of the NILs carrying 22 glutenin subunit was higher than that of the NILs carrying the 7+9 glutenin subunit (20.4% and 16.2%, respectively). In contrast, the NILs with 22 glutenin subunit had a lower sedimentation volume than those of the NILs with 7+9 glutenin subunits. The 22 glutenin subunit decreased the sedimentation volume from 19.47 to 13.49 mL. The average GSI value of the NILs carrying 7+9 glutenin subunits was higher than that of the NILs carrying 22 glutenin subunit (3.05 and 2.92). In conclusion, in this study we were able to detect a quality difference between NILs with 22 and 7+9 glutenin subunits in a small amount of samples. These findings suggest that glutenin subunit 22 may be associated with low gluten strength.

Assessing Payne score accuracy through a bread wheat multi-genotype and multi-environment set from CIMMYT

The Payne score is a prevalent strategy for assessing wheat quality by considering the distinct contributions of specific high-molecular-weight glutenin subunits. Despite its extensive use, the limited germplasm used in its development (84 British cultivars from the early 1980s) may limit its accuracy when is applied to other type of germplasm. Here we tested the Payne score accuracy and related scales using an extensive dataset. The precision of the scale is higher for Glu-A1 and Glu-D1 loci, particularly when predicting dough strength, and loaf volume. However, for dough extensibility, the accuracy decreased. For Glu-B1 it could discriminate differences to some extent, but higher scores did not always correspond to higher quality values, and vice versa. When the total Payne score was evaluated, the most pronounced degree of differentiation between scale values was observed for gluten strength related traits. When analyzing the total Payne score for various haplotypes, higher values for gluten strength, and loaf volume generally corresponded to higher Payne scores; however, some samples with low values were ranked with the highest scores and vice versa. Our findings suggest that there is a probability of selecting cultivars with high Payne scores that do not match the desired quality.

Structure Strengthening Phenomena of Gluten Matrices under Different Stress Types.

To predict the achievable product volume with respect to the gas retention capacity of the gluten matrix in wheat flour doughs, strain hardening evaluation is crucial. But assessing these structure hardening phenomena in wheat flour dough systems is still a challenging task. In this work, a simple shear method applied to kneaded dough samples was tested and compared to biaxial extension tests performed with a lubricated squeezing flow method. The comparability of shear-induced structure hardening with biaxial extension tests was shown. Structure hardening and breakdown after overload were visualized using shear flow and a comparison of the obtained shear flow over Hencky strain curve peaks. To predict the behavior of the analyzed flours according to their composition, a correlation analysis of the flour and dough properties was performed. The influence of the HMW glutenin subunits on the sensitivity of the dough matrix according to the applied shear speed (0.1 and 1.0 mm/s) could be shown with a correlation coefficient of 0.94. The LMW glutenin subunits, on the other hand, showed a high correlation coefficient of 0.89 with the achievable network connectivity parameter z [-] gained from frequency sweep testing.

Development of a Set of Wheat-Rye Derivative Lines from Hexaploid Triticale with Complex Chromosomal Rearrangements to Improve Disease Resistance, Agronomic and Quality Traits of Wheat.

An elite hexaploid triticale Yukuri from Australia was used as a bridge for transferring valuable genes from Secale cereale L. into common wheat for enriching the genetic variability of cultivated wheat. Non-denaturing-fluorescence in situ hybridization (ND-FISH) identified that Yukuri was a secondary triticale with a complete set of rye chromosomes and a 6D(6A) substitution. Seed protein electrophoresis showed that Yukuri had a unique composition of glutenin subunits. A set of Yukuri-derived wheat-rye introgression lines were created from a Yukuri x wheat population, and all lines were identified by ND-FISH with multiple probes and validated by diagnostic molecular marker analysis. A total of 59 wheat-rye introgression lines including modified chromosome structural variations of wheat, and new complex recombinant chromosomes of rye were detected through ND-FISH and Oligo-FISH painting based on oligonucleotide pools derived from wheat-barley genome collinear regions. Wheat lines carrying the 1R chromosome from Yukuri displayed resistance to both stripe rust and powdery mildew, while the lines carrying the 3RL and 7RL chromosome arms showed stripe rust resistance. The chromosome 1R-derived lines were found to exhibit a significant effect on most of the dough-related parameters, and chromosome 5R was clearly associated with increased grain weight. The development of the wheat-rye cytogenetic stocks carrying disease resistances and superior agronomic traits, as well as the molecular markers and FISH probes will promote the introgression of abundant variation from rye into wheat improvement programs.

Study of Baking Quality and Determination of High Molecular Weight Glutenin Subunits (HMW-GS) of Local and Introduced Wheat Varieties

The baking qualities of 36 varieties of wheat are considered. Storage proteins — high molecular weight glutenin subunits (HMW-GS) — were studied. Electropherograms were processed in the GelPro Analyzer 4.0 computer program. The molecular weight of glutenin subunits was determined according to the method of G. Galili, M. G. Feldman using a marker variety. The quality of glutenin was assessed in points according to the method of O. Lukov. The bread was baked using the straight method, in accordance with the generally accepted method of laboratory baking; the fermentation of the dough and further baking were carried out on Domino and Arianna devices. As a result of the research, it was revealed that only 7 test samples (Askeran, Azemetli 95, Gonen, Gyrmyzy Gul, Nurlu99, Tale38, Ugur) with a null allele, having subunit 1 (Glu-A1a allele), have a fragment of 344 bp in size, in the remaining 29 samples encoded by the Glu-A1 locus, having subunit 2* (Glu-A1b allele), a fragment of 362 bp in size is amplified. The presence of a null allele does not always have a negative effect on baking quality. The reason for this remains to be determined.

Identifying cis-Acting Elements Associated with the High Activity and Endosperm Specificity of the Promoters of Genes Encoding Low-Molecular-Weight Glutenin Subunits in Common Wheat (Triticum aestivum).

Low-molecular-weight glutenin subunits (LMW-GSs) associated with bread-baking quality and flour nutrient quality accumulate in endosperms of common wheat and related species. However, the mechanism underlying the expression regulation of genes encoding LMW-GSs has not been fully elucidated. In this study, we identified LMW-D2 and LMW-D7, which are highly and weakly expressed, respectively, via the analysis of RNA-sequencing data of Chinese Spring wheat and wheat transgenic lines transformed with 5' deletion promoter fragments and GUS fusion constructs. The 605-bp fragment upstream of the LMW-D2 start codon could drive high levels of GUS expression in the endosperm. The truncated endosperm box located at the -300 site resulted in the loss of LMW-D2 promoter activity, and a single-nucleotide polymorphism on the GCN4 motif was closely related to the expression of LMW-GSs. TCT and TGACG motifs, as well as the others located on the 5' distal end, might also be involved in the transcription regulation of LMW-GSs. In transgenic lines, fusion proteins of LMW-GS and GUS were deposited into protein bodies. Our findings provide new insights into the mechanism underlying the transcription regulation of LMW-GSs and will contribute to the development of wheat endosperm as a bioreactor for the production of nutraceuticals, antibodies, vaccines, and medicinal proteins.

Partial C-terminal truncation of Bx and Dy high molecular weight glutenin subunits after conserved aspartate

The composition of polymeric gluten proteins and interaction with non-covalently associated gliadins define the functional utility of a flour. This composition is dictated by the timing of cellular and genetic events in the plant and the developing seed. This interplay and its effect on gluten functionality is poorly understood and could provide a new opportunity for improving wheat quality in the future. Truncated proteoforms of high-molecular weight glutenin subunits (HMWGS) were observed for Bx and Dy subtypes across 49 Canadian bread wheat and 16 durum varieties. The relative abundances of these variants ranged from 7.5% to 37.7% and abundances of Bx and Dy variants were highly correlated (r2 = 0.85). HMWGS Bx7* and Dy10 were purified and the mass difference was shown to be from the loss of a C-terminal hexapeptide after a conserved aspartate residue. This aspartate was present at the ω-7 position in >90% of HMWGS accessions and the C-terminal sequence was highly conserved. Importantly, all HMWGS subtypes contain the same conserved sequences, but truncated variants were never observed for By, Dx and Ax HMWGS. The potential impact of these truncated HMWGS on gluten form and function is discussed.

Genetic diversity of bread wheat (Triticum aestivum L.) in the allelic composition of HMW-GS (a review)

Background. The qualitative composition of wheat grain varies depending on the cultivar, soil and climate conditions, and agricultural practices. The allelic composition of glutenins in bread wheat cultivars is an important parameter for the analysis and management of their genetic structure. In this respect, there is an interest in studying the genetic diversity of alleles of high-molecular-weight glutenin subunits (HMW-GS) in bread wheat cultivars from Europe, Asia, Africa, and America.Materials and methods. The total diversity of alleles in Glu-1 glutenin loci was evaluated according to the calculation of the Nei index (H). Using this indicator and the cluster analysis, wheat cultivars of various ecogeographic origin were distributed into relatively homogeneous groups.Results. Wheat cultivars from Poland, Germany, France, Spain, Portugal, Turkey, Iran, Pakistan, India, China, and Algeria (Group I) had the average Nei index of 0.59, and those from the U.S., Mexico, Argentina, Russia, Kazakhstan, Ethiopia, Czech Republic, Hungary, Bulgaria, Afghanistan, and North Korea (Group II) had 0.42. These groups of wheat cultivars differed in the frequency of occurrence of glutenin subunits at each Glu-1 locus: N, 7+9, 2+12 in Group I, and 2*, 7+9, 5+10 in Group II.Conclusion. Wheat cultivars from Group II had on average a low level of variability of allelic genes in the respective loci, manifesting high grain quality of these cultivars and the highest probability of their genetic depletion compared to the cultivars from Group I, where most of the cultivars are described by a combination of low-quality glutenin subunits.

Effect of different enzymes on thermal and structural properties of gluten, gliadin, and glutenin in triticale whole-wheat dough

Three enzymes promoted the development of the gluten network in triticale whole-wheat noodles (TWWN). To further understand the mechanism of gluten enhancement, the effects of three enzymes on the structure of gluten and its fractions (gliadin and glutenin) were evaluated. The results showed that glucose oxidase (GOD), xylanase (XYL), and laccase (LAC) decreased the content of sodium dodecyl sulfate (SDS) extractable proteins. The content of glutenin subunits was reduced by 17.25 %, 30.60 %, and 20.09 % with the addition of GOD, XYL, and LAC, respectively. Furthermore, GOD and LAC increased the content of glutenin macropolymer (GMP) by 2.64 % and 7.71 %, respectively, suggesting the promotion of glutenin aggregation. The addition of three enzymes decreased the weight loss and increased the degradation temperature of the gluten and its fractions. GOD and XYL decreased the fluorescence intensity of gluten and its fractions, except for XYL which increased the fluorescence intensity of glutenin by 10.50 %. Intermolecular interactions and surface hydrophobicity were enhanced by XYL in gluten and its fractions. GOD and LAC decreased the free sulfhydryl content and increased the β-sheet content, suggesting that the covalent interaction between gluten fractions was enhanced. Therefore, this research can enrich the theoretical study of enzymatic cross-linking.

Regulating the composition and secondary structure of wheat protein through canopy shading to improve dough performance and nutritional index

Viscoelastic properties of gluten proteins critically determine the biscuit-making quality. However, cultivar genetics and light conditions closely regulate the composition of the gluten proteins. The impact of pre- and post-anthesis shading (60 %) on amino acid profile, gluten protein composition, secondary structure, dough performance, and biscuit-making quality were evaluated using four wheat cultivars that differ in gluten protein composition. Pre- and post-anthesis shading increased the contents of gliadin, by 35.8 and 3.1 %; glutenin, by 27.6 and 7.3 %; and total protein, by 21.7 and 10.6 %, respectively, compared with those of unshaded plants. Conversely, the ratios of glutenin/gliadin, ω-/(α,β + γ)-gliadin, and high-molecular-weight/low-molecular-weight glutenin subunits decreased with shading. Strong-gluten cultivars exhibited smaller declines in these parameters than weak-gluten cultivars. Secondary structure analysis of the wheat protein revealed that shading increased β-sheet content but decreased β-turn content. Changes in protein components and their secondary structures caused an increase in wet gluten content, dough development time, and gluten performance index, thereby decreasing the biscuit spread ratio. Shading stress increased the protein content and nutrition index but decreased the biological value of protein by 2.5 %. Transcriptomic results revealed that shading induced 139 differentially expressed genes that decreased carbohydrate metabolism and increased amino acid metabolism, involved in increased protein content. Thus, canopy shading improves dough performance and nutrition index by regulating the amino acid profiles, protein compositions, and secondary structures. The study provides key insights for achieving superior grain quality under global dimming.

Effects of Low-Molecular-Weight Glutenin Subunit Encoded by Glu-A3 on Gluten and Chinese Fresh Noodle Quality.

Low-molecular-weight glutenin subunits (LMW-GS) account for 40% of the total wheat grain gluten protein fraction, which plays a significant role in the formation of noodle processing quality. The goal of this study was to clarify the effects of the major LMW-GS encoded by Glu-A3 on gluten and Chinese fresh noodle (CFN) quality. Four near-isogenic lines (NILs) were used as materials in this study, respectively carrying alleles Glu-A3a, Glu-A3b, Glu-A3c, and Glu-A3e, against the background of wheat variety Xiaoyan 22. The grain protein and its component contents and the gluten content, gluten index, farinograph properties, cooking quality, and textural quality of CFN were investigated. The results show that the ratios of glutenin to gliadin (Glu/Gli) in the NILs ranked them as Glu-A3b > Glu-A3c/Glu-A3a > Glu-A3e, and the unextractable polymeric protein content (UPP%), gluten index (GI), and farinograph quality in the NILs ranked them as Glu-A3b > Glu-A3c > Glu-A3a/Glu-A3e. Compared to Glu-A3b and Glu-A3a, the NILs carrying alleles Glu-A3c and Glu-A3e had better cooking and texture properties in CFN. All these findings suggest that the introduction of alleles Glu-A3c or Glu-A3e is an efficient method for quality improvement in CFN, which provides an excellent subunit selection for improving CFN quality.

Genetic polymorphism of high-molecular-weight glutenin subunit loci in bread wheat varieties in the Pre-Ural steppe zone.

High-molecular-weight glutenins play an important role in providing high baking qualities of bread wheat grain. However, breeding bread wheat for this trait is very laborious and, therefore, the genotyping of variety samples according to the allelic composition of high-molecular-weight glutenin genes is of great interest. The aim of the study was to determine the composition of high-molecular-weight glutenin subunits based on the identification of the allelic composition of the Glu-1 genes, as well as to identify the frequency of the Glu-1 alleles in bread wheat cultivars that are in breeding work under the conditions of the Pre-Ural steppe zone (PSZ). We analyzed 26 winter and 22 spring bread wheat varieties from the PSZ and 27 winter and 20 spring varieties from the VIR collection. Genotyping at the Glu-A1 locus showed that the Ax1 subunits are most common in winter varieties, while the predominance of the Ax2* subunits was typical of spring varieties and lines. In the Glu-B1 locus, the predominance of alleles associated with the production of the Bx7 and By9 subunits was revealed for both winter and spring varieties. In the case of the Glu-D1 gene, for all the wheat groups studied, the composition of the Dx5+Dy10 subunits was the most common: in 92.3 % of winter and 68.2 % of spring PSZ accessions and in 80 % of winter and 55 % of spring VIR accessions. The analysis of genotypes showed the presence of 13 different allelic combinations of the Glu-A1, Glu-B1, Glu-D1 genes in the PSZ varieties, and 19 combinations in the VIR varieties. The b b/al/с d allelic combination (Ax2* Вх7+Ву8/8*/9 Dx5+Dy10) turned out to be the most common for the PSZ spring varieties and lines, while for the PSZ winter accessions it was a с d (Ax1 Вх7+By9 Dx5+Dy10); the b с a and b с d genotypes (Ax2* Вх7+Ву9 Dx2+Dy12 and Ax2* Вх7+Ву9 Dx5+Dy10, respectively) occur with equal frequency among the VIR spring accessions; in the group of VIR winter varieties, the combination of the a b/ al d alleles (Ax1 Вх7+Ву8/8* Dx5+Dy10) prevails. The most preferred combination of alleles for baking qualities was found in the spring variety 'Ekaterina' and winter varieties 'Tarasovskaya 97', 'Volzhskaya S3', as well as in lines k-58164, L43510, L43709, L-67, L-83, which are recommended for further breeding programs to improve and preserve baking qualities in the conditions of the Pre-Ural steppe zone.