High Molecular Weight Glutenin Subunit Composition Research Articles

Composition of high-molecular-weight glutenin subunits and gluten quality in wheat lines with alien genetic material

Background. High-molecular-weight glutenin subunits (HMW-GSs) make the greatest contribution to the formation of baking properties in bread wheat (Triticum aestivum L.). Glutenin polymorphism of bread wheat relatives is significantly richer than in cultivated varieties. The objective of this work was to identify the HMW-GS composition and assess the gluten quality of bread wheat lines with introgressions of alien genetic material.Materials and methods. We studied the parental varieties of spring bread wheat, accessions of the tetraploid and hexaploid Triticum L. species, and 19 introgressive lines produced with their participation. Glutenins were separated using sodium dodecyl sulfate polyacrylamide gel electrophoresis and HMW-GSs were identified using the Payne nomenclature system. Gluten quality was determined in accordance with GOST 13586.1-68 (the 2017–2019 and 2021–2022 growing seasons). Data processing was performed using the Statistica 10.0 and MS Excel software packages.Results and conclusion. HMW-GSs uncharacteristic of T. aestivum cultivars were identified in the studied accessions of T. dicoccoides (Körn. ex Aschers. et Graebn.) Schweinf., T. spelta L., and T. kiharae Dorof. et Migusch. These HMW-GSs are of interest for enriching the wheat gene pool. HMW-GSs of related species were found in 10 out of 19 introgressive lines. A five-year observation period revealed that wheat relatives on average significantly exceeded common wheat cultivars in gluten quality, and introgressive lines did not differ significantly from the parental genotypes. Lines with high rheological properties of gluten had, as a rule, HMW-GSs of related species in their composition.

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.

Addition of Psathyrostachys huashanica HMW glutenin subunit expresses positive contribution to protein polymerization and gluten microstructure of receptor wheat

Psathyrostachys huashanica Keng (2n = 2x = 14, NsNs) is considered as a valuable wild germplasm for wheat improvement on account of its numerous outstanding traits. During this study, 7182-1Ns with higher quality was screened out, a series of experiments were conducted to clarify the reasons of quality improvement. The results indicated 7182-1Ns was carried a novel high-molecular-weight glutenin subunit (HMW-GS) from P. huashanica, designated as P. huashanica’ subunit in wheat (HS), which changed the HMW-GS compositions, increased the proportion of glutenins in wheat gluten protein, accelerated the accumulation speed of unextractable polymeric protein (UPP) during grain development stage accelerated, and a denser microstructure of the gluten network was formed in the dough. Therefore, the current research provides important reference on effectively utilize 7182-1Ns as an intermediate germplasm for quality breeding improvement.

Enhancing Wheat Flour Quality Through Introgression of High-Molecular-Weight Glutenin Subunits From Aegilops tauschii Accessions

Narrow genetic diversity in the wheat gene pool restricts the improvement of wheat quality traits. Aegilops tauschii possesses valuable genetic diversity that can be used to improve not only biotic and abiotic stresses in arid regions but also wheat yield and quality. Our study, which used 392 multiple synthetic derivatives (MSD) panel developed with Ae. tauschii Coss. introgressions, had three main aims: to explore the genetic diversity of high-molecular-weight glutenin subunits (HMW-GS), to investigate the dough strength and the relationship between protein content and grain yield, and to identify lines with a good flour quality. A wide range of allelic diversity was observed at the Glu-D1 locus, reflecting the impact of the different introgressed portions of Ae. tauschii, and a wide variation was found in dough strength even between lines having the same composition of HMW-GS. We report a negative impact on dough strength of subunit 5t+10t from Ae. tauschii and a relatively positive impact of subunit 2t+12.1t. We identified four MSD lines with significantly enhanced flour quality. Regressing the grain yield of the MSD lines against protein content showed no correlation between the two traits and identified lines with comparable grain yield to the recurrent parent and higher protein content. The identified MSD lines could provide a valuable genetic resource for enhancing the end-use quality of flour without any loss in productivity.

Interaction of B-type starch with gluten skeleton improves wheat dough mixing properties by stabilizing gluten micro-structure

Some recent studies have revealed individual and the combined interactions of gluten and starch affecting dough mixing properties. However, the combined influence of high-molecular-weight glutenin subunits (HMW-GS) and starch on dough mixing and rheological properties requires elucidation. Thus four recombinant inbred lines, SS 1, SS 2, ZZ 1 and ZZ 2, were selected based on their HMW-GSs compositions. Compared to ZZ 1 and ZZ 2, both SS 1 and SS 2 carried superior HMW-GS alleles, and exhibited extended dough development and stability time, indicating their significant dough mixing characteristics. The gluten skeleton of the wheat lines SS 2 and ZZ 2 with higher B-type starch proportions exhibited fewer breakages along with the rise of dough temperature during mixing. Higher content of B-type starch strengthens interaction between starch and gluten skeleton at the dough heating stage, suggesting a specific range of B-type starch proportion can improve dough mixing characteristics.

Effects of HMW-GSs on quality related traits in wheat (Triticum aestivumL.) under different water regimes.

Alleles at the Glu-1 loci play important roles in the functional properties of wheat flour. The effects of various high-molecular-weight glutenin subunit (HMW-GS) compositions on quality traits and bread-making properties were evaluated using 235 doubled haploid lines (DHs). The experiment was conducted in a split plot design with two water regimes as the main plot treatment, and DH lines as the subplot treatments. Results showed that the presence of subunit pair 5+10 at the Glu-D1 locus, either alone or in combination with others, appears to provide an improvement in quality and bread-making properties. At the Glu-A1 locus, subunit 1 produced a higher Zeleny sedimentation value (Zel) and stretch area (SA) than subunit 2* when subunits 14+15 and 5+10 were expressed at the Glu-B1 and Glu-D1 loci, and 2* had a positive effect on the maximum dough resistance (Rmax) when subunits 14+15 and 5'+12 were expressed at the Glu-B1 and Glu-D1 loci, respectively. Given subunit 1 at the Glu-A1 locus and 5'+12 at the Glu-D1 locus, the effects of Glu-B1 subunits 14+15 on the tractility (Tra), dough stability time (ST), and dough development time (DT) under the well-watered regime were significantly higher than those of Glu-B1 subunits 13+16. However, 13+16 had a positive effect on SA under the rain-fed regime when subunits 2* and 5+10 were expressed at the Glu-A1 and Glu-D1 loci, respectively. Multiple comparisons analysis revealed that the Zel and Rmax of the six subunits and eight HMW-GS compositions were stable under different water regimes. Overall, subunit compositions 1, 13+16 and 5+10 and 1, 14+15 and 5+10 had higher values for quality traits and bread-baking properties under the two water regimes. These results could play a positive guiding role in selecting and popularizing varieties suitable for production and cultivation in local areas.

Influences of high-molecular-weight glutenin subunits and rye translocations on dough-mixing properties and sugar-snap cookie-baking quality of soft winter wheat.

The significance of high-molecular-weight glutenin subunits (HMW-GSs) and rye translocations, and their associations with gluten strength for hard wheat used for making bread has been understood well, but remains poorly understood for soft wheat used for making cookies. The influences of HMW-GSs and rye translocations on the dough-mixing properties and cookie-baking quality of soft wheat were investigated using 50 US eastern soft winter (ESW) wheat varieties possessing 14 predominant HMW-GS profiles. Glu-A1 and Glu-B1 loci only influenced dough-mixing properties significantly, whereas the Glu-D1 locus influenced both dough-mixing properties and cookie-baking quality significantly. The subunits 1, 7* + 8 and 5 + 10 at the Glu-A1, Glu-B1 and Glu-D1 loci, respectively, were associated with a long midline peak time, whereas only the rare subunits 2 + 121 at the Glu-D1 locus exhibited significant associations with improved cookie-baking quality of ESW wheat. The contributions of rye translocations to dough-mixing properties and cookie-baking quality depended on HMW-GS profiles. Three HMW-GS profiles (2*, 7 + 9, 2 + 121 ), (2*, 7 + 8, 2 + 121 ) and (1, 7 + 8, 2 + 121 ) were identified as being desirable for making large-diameter cookies. Flour protein content, lactic acid (LA), and sodium carbonate (SC) solvent retention capacities and softness equivalence were identified as effective predictors of cookie diameter and accounted for 79% of the variation in cookie diameter. Subunits 2 + 121 have significant associations with the protein characteristics and cookie-baking quality of soft wheat. The determination of HMW-GS composition would be an effective tool in soft-wheat breeding programs for quickly identifying and selecting acceptable breeding lines possessing desirable cookie-baking potential. Published 2020. This article is a U.S. Government work and is in the public domain in the USA.

Gene-ecology of durum wheat HMW glutenin reflects their diffusion from the center of origin

The production of many food items processed from wheat grain relies on the use of high gluten strength flours. As a result, about 80% of the allelic variability in the genes encoding the glutenin proteins has been lost in the shift from landraces to modern cultivars. Here, the allelic variability in the genes encoding the high molecular weight glutenin subunits (HMW-GSs) has been characterized in 152 durum wheat lines developed from a set of landraces. The allelic composition at the two Glu-1 loci (Glu-A1 and -B1) was obtained at both the protein and the DNA level. The former locus was represented by three alleles, of which the null allele Glu-A1c was the most common. The Glu-B1 locus was more variable, with fifteen alleles represented, of which Glu-B1b (HMW-GSs 7 + 8), -B1d (6 + 8) and -B1e (20 + 20) were the most frequently occurring. The composition of HMW-GSs has been used to make inferences regarding the diffusion and diversification of durum wheat. The relationships of these allelic frequencies with their geographical distribution within the Mediterranean basin is discussed in terms of gene-ecology.

Allelic variation of high molecular weight glutenin subunits of bread wheat in Hebei province of China

In common wheat (Triticum aestivum L.), allelic variations of Glu-1 loci have important influences on grain end-use quality. The allelic variations in high molecular weight glutenin subunits (HMW-GSs) were identified in 151 hexaploid wheat varieties representing a historical trend in the cultivars introduced or released inHebei province ofChina fromthe years 1970s to 2010s.Thirteen distinct alleles were detected for Glu-1. At Glu-A1, Glu-B1 and Glu-D1, we found that the most frequent alleles were the 1 (43.0%), 7+8 (64.9%), 2+12 (74.8%) alleles, respectively, in wheat varieties. Twenty two different HMW-GS compositions were observed in wheat. Twenty-five (16.6%) genotypes possessed the combination of subunits 1, 7+8, 2+12, 25 (16.6%) genotypes had subunit composition of 2*, 7+8, 2+12; 20 (13.2%) genotypes had subunit composition of null, 7+8, 2+12. The frequency of other subunit composition was less than 10%. The Glu-1 quality score greater than or equal to 9 accounted for 20.6% of the wheat varieties. The percentage of superior subunits (1 or 2* subunit at Glu-A1 locus; 7+8, 14+15 or 17+18 at Glu-B1 locus; 5+10 or 5+12 at Glu-D1 locus) was an upward trend over the last 40 years. The more different superior alleles correlated with good bread-making quality should be introduced for their usage in wheat improvement efforts.

Effect of high-molecular-weight glutenin subunit deletion on soft wheat quality properties and sugar-snap cookie quality estimated through near-isogenic lines

High-molecular-weight glutenin subunits (HMW-GSs) play a critical role in determining the viscoelastic properties of wheat dough. The HMW-GSs are encoded by Glu-A1, Glu-B1, and Glu-D1 loci on the long arms of chromosomes 1A, 1B, and 1D, respectively. In the present study, four near-isogenic lines with different HMW-GS deletions and compositions at the Glu-A1 and Glu-D1 loci in Yangmai 18 background were used for quality analysis. Deletion in Glu-D1 showed much weaker gluten quality and dough strength than null Glu-A1 genotype and wild genotype (WT), based on the measurements of sodium dodecyl sulfate (SDS)-sedimentation, lactic acid solvent retention capacity (SRC), gluten index, development time, stability time, and alveograph P and L values. The deletion of Glu-D1 did not significantly affect grain hardness, grain protein content, water SRC, sodium carbonate SRC, and sucrose SRC. Double null genotype in Glu-A1 and Glu-D1 and single null genotype in Glu-D1 showed significantly higher cookie diameter, crispness, and lower cookie height compared with single null genotype in Glu-A1 and WT. These indicate that the null Glu-D1 genotype is useful for improvement of biscuit quality, and use of this germplasm would be a viable strategy to develop new wheat varieties for biscuit processing.

Identification of spring wheat genotypes by glutenin and gliadin subunit composition within the Kazakhstan-Siberia network of nurseries

The Kazakhstan-Siberia nursery (KASIB) for the spring wheat improvement under the aegis of the CIMMYT (International Maize and Wheat Improvement Center) has been identified for a ten-year period by five cultivar blocks analyzed for the gliadin composition (1B/1R traslocation), compositions of high-molecular weight (HMW) and low-molecular weight (LMW) glutenin subunits, and the grain hardness class. A composition of HMW glutenin subunits is presented according to the Union for Protection of New Varieties of Plants (UPOV) regulations for characteristics 27, 28, and 29 of the system for testing the uniformity, distinctness, and stability of 188 uniform specimens. Most spring wheat varieties are characterized by the formulas “2* 7 + 9 5 + 10” (up to 40% of all uniform varieties), “2* 7 + 9 2 + 12” (up to 30% of all uniform varieties), and “1 7 + 95 + 10” (up to 8% of specimens). In the Kazakhstan gene pool of varieties, the genotypes with the novel 4 + 10 subunit on the 1D chromosome has been detected in the Erythrospermum 55/94-01-20 and Phyton 41 specimens. The Iridost cultivar is identified as a carrier of the comparatively rare 5.5 + 10 allele on the 1D chromosome, which has been previously detected in the Tselinogradka, Tselinnaya 24, and Akmola 3 varieties. A rare 7* + 8 subunit is typical for the E-607 and E-757 genotypes. The specimen uniformity level is the highest in 3 KASIB components (8, 9; 10–11; and 12, 13) and comprises 74–84%. The wheat-rye 1 BL.1RS translocation is predominantly identified in specimens selected at the Siberian Research Institute of Agriculture (SibNIISKhOZ) and the East-Kazakhstan Research Institute of Agriculture (VKNIISKh) and found at each KASIB block; it is indicated in all specimens presented by the Kurgansemena Close Corporation and the Agrosemconsult, LLP, as well as selected at the Fiton, LLP. Cultivars such as Altaiskaya 105, Kurganskaya 5, Lutecsence 1300, Phyton 42, Lutecsence 53/95-98-1, Lutecsence 53/88-94-12, Lutecsence 54, Lutecsence 30–94, Erythrospermum 607, and Aktobe 1574 have been characterized by a wide range of variation in grain hardness from semisoft to hard under different growth conditions.

Characterization of high molecular weight glutenin subunits of Wheat genotypes

End use quality of wheat is an important goal for developing elite genotypes. Glutenins are considered key factors in improving processing quality, particularly high molecular weight glutenin subunits (HMW-GS). The HMW-GS are known to be encoded by three Glu-1 loci located on the long arms of chromosomes 1A, 1B and 1D. The endosperm storage proteins of 90 advanced breeding lines developed for peninsular zone of India were analysed by SDS-PAGE to determine their HMW-GS compositions. A total of ten alleles were identified: three at Glu-A1 , five at Glu-B1 , and two at Glu-D1 . In Glu-A1 locus, null, 1 and 2* alleles were found with the frequency of 48%, 30% and 22%. Whereas, in Glu-B1 , 5 alleles with frequency of 17+18 (33%), 7+9 (27%), 7 (25%), 6+8 (9%), and 20 (6%) were detected. In Glu-D1 locus, 2+12 and 5+10 were marked with the frequency of 60% and 40%, respectively. Quality score of genotypes were ranged from 4 to 10, with an average of 6.95 indicating vast genetic diversity among the genotypes. The presence of subunits combinations in different varieties with low, medium and high gluten strength revealed that breeding wheat for bread, chapatti and biscuits is possible as per end use requirement.

Influence of high-molecular-weight glutenin subunit composition at Glu-B1 locus on secondary and micro structures of gluten in wheat (Triticum aestivum L.)

Glutenin is one of the critical gluten proteins that affect the processing quality of wheat dough. High-molecular-weight glutenin subunits (HMW-GS) affect rheological behavior of wheat dough. This research demonstrated the effects of four variations of HMW-GS composition at the Glu-B1 locus on secondary and micro structures of gluten and rheological properties of wheat dough, using the bread wheat Xinong 1330 and its three near-isogenic lines (NILs). Results indicated that the Amide I bands of the four wheat lines shifted slightly, but the secondary structure, such as content of α-helices, β-sheets, disulfide bands, tryptophan bands and tyrosine bands, differed significantly among the four NILs. The micro structure of gluten in NIL 2 (Bx14+By15) and NIL 3 (Bx17+By18) showed more cross linkage, with two contrasting patterns. Correlation analysis demonstrated that the content of β-sheets and disulfide bonds has a significant relationship with dough stability, which suggests that the secondary structures could be used as predictors of wheat quality.

Towards the understanding of end-use quality in intermediate wheatgrass (Thinopyrum intermedium): High-molecular-weight glutenin subunits, protein polymerization, and mixing characteristics

Intermediate wheatgrass (Thinopyrum intermedium; IWG), is a perennial crop that is well-known for providing good environmental services. As a perennial relative of wheat, IWG has good potential for development into a perennial grain crop. But the diversity and potential of the end-use quality of IWG grain are still unknown. Here, to understand the end-use quality of IWG, we investigated the variability among seed from 60 IWG genotypes in high-molecular-weight glutenin subunits (HMW-GS), protein polymerization, and mixing characteristics. IWG genotypes have high grain protein content, ranging from 16.4 to 23.6%. Of the total proteins, the percentage of polymeric proteins show a large range across IWG genotypes, varying from 9.2 to 25.1%. Many genotypes have limited amounts of polymeric proteins, but several genotypes have large amounts of polymeric proteins and promising mixing properties, comparable to common wheat, Triticum aestivum. The amount of protein polymers in the SDS buffer unextractable fraction are significantly correlated (r ≥ 0.76) with mixograph parameters. Furthermore, we observed that HMW-GS variants showed differential contribution to protein polymerization and mixograph parameters. But the composition of HMW-GS in IWG was contributed by both parents, which might bring challenges for the evaluation of grain quality of open-pollinated IWG genotypes.

Special HMW-GSs and their genes of Triticum turgidum subsp. dicoccoides accession D141 and the potential utilization in common wheat

High molecular weight glutenin subunits (HMW-GSs) are the critical components of wheat seed storage proteins. They play a crucial role in determining dough viscoelastic properties and end-use quality of wheat flour. To investigate the potential utilization of the special HMW-GSs from wild emmer wheat (2n = 4x = 28, AABB) accession D141 in common wheat (2n = 6x = 42, AABBDD), continued to our previous report of the 1Ay and its coding sequence, the other three HMW-GSs, 1Ax, 1Bx13.1 and 1By16.1, and their coding genes were isolated, characterized and transferred from D141. The 1Ax gene was silent because of containing a premature stop codon TGA at position 835–837. The ORFs of 1Bx13.1 and 1By16.1 were 2373 and 2157 bp in length, and encoded 789 and 717 amino acid residues, respectively. Compared with the other 20 Glu-1Bx alleles in GenBank, seven SNPs and one 18-bp deletion were detected in 1Bx13.1. Compared with the other 10 Glu-1By alleles in GenBank, nine SNPs were observed in 1By16.1. The mobility of 1Bx13.1 and 1By16.1 on the SDS-PAGE gel was most similar to that of 1Bx13 and 1By16 from common wheat (T. aestivum, 2n = 6x = 42, AABBDD) cv. ‘Jimai 20′, respectively. Protein secondary structure prediction showed that the combination of 1Bx13.1 + 1By16.1 possessed more α-helixes with more amino acid residues than that of 1Bx13 + 1By16. It suggested that 1Bx13.1 + 1By16.1 from wild emmer accession D141 might have more positive effects on bread-making quality than the superior subunit combination 1Bx13 + 1By16. The HMW-GS composition analysis of F1 and F2 between common wheat for female and wild emmer accession D141 for male, indicated that the special HMW-GSs from wild emmer accession D141 could be easily introduced into common wheat (2n = 42) by general inter-species hybridization.

Allelic variations of functional markers for high molecular weight glutenin genes in Indian wheat (Triticum aestivum L.) cultivars and their correlation with bread loaf volume

Glutenins, the polymeric proteins are composed of high molecular weight (HMW) and low molecular weight (LMW) glutenin subunits. High molecular weight glutenin subunit (HMW-GS) plays a key role in determining bread making quality. The HMW-GS encoded by Glu-1 loci (GluA1, GluB1 and GluD1) are highly polymorphic. Thus it is very important to identify the alleles at Glu-1 loci for all three genomes for wheat quality improvement. In the present study 53 Indian wheat genotypes were evaluated for HMW-GS composition using PCR-based DNA markers. In total, two alleles (Ax2*, Ax1 or Axnull) at Glu-A1, four allele/allelic pairs (Bx7, Bx7 + By8, Bx7 + By9, Bx17 + By18) at Glu-B1 and two allelic pairs (Dx2 + Dy12 and Dx5 + Dy10) at Glu-D1 were identified using diagnostic DNA markers. Allele or allelic pair Ax2* (62.3 %) at Glu-A1, Bx7 + By8 (64 %) at Glu-B1 and Dx2 + Dy12 (58.5 %) at Glu-D1 were present most frequently in wheat genotypes taken for study. Moreover, the allelic combination Ax2*, Bx17 + By18 and Dx5 + Dy10 exhibited highest bread loaf volume in comparison to other allelic combinations studied. The set of markers used here thus represents a useful alternative for screening of HMW-glutenin allele (s) for improvement of bread making quality in Indian wheat genotypes.

Identification and evaluation of disease resistance and HMW-GS composition of Aegilops geniculata Roth

Aegilops geniculata Roth is an important germplasm resource for the transfer of beneficial genes from alien species of wheat into common wheat (Triticum aestivum L.). In this study, we identified and evaluated agronomic characters, powdery mildew resistance, stripe rust resistance, and high molecular weight glutenin subunit (HMW-GS) compositions of 44 Ae.geniculata accessions. The average growth period (254 days) was longer than that of common wheat (240 days). Coefficients of variation (CVs) of all examined agronomic characters except growth period were >10 %. The largest CV, 23.80 %, was that of 1,000-grain weight. An assay for disease resistance revealed that 37 Ae.geniculata accessions (85.09 %) were resistant to powdery mildew, of which 33 were immune, 1 was highly resistant, and 3 were moderately resistant. This assay also indicated that 33 of the accessions (75 %) were resistant to stripe rust, with 25 showing immunity, 4 highly resistant, and 4 moderately resistant. Additionally, 19 accessions (43.18 %) were immune to both powdery mildew and stripe rust. HMW-GSs in the 44 accessions were analyzed by SDS polyacrylamide-gel electrophoresis, which indicated rich germplasm diversity. A total of 21 different HMW-GS alleles were identified at Glu-1 loci. The most frequent subunits were 1Dx2, 1Dx1.1, 1Dx2.2, 1Dx1.5, 1Bx20, 1Bx22, 1Dy10, and 1Dy12, found in 36.36, 54.55, 40.91, 34.09, 38.64, 25.00, 47.73, and 20.45 % of accessions, respectively. The data uncovered for the 44 accessions should facilitate their use as beneficial germplasm donors in wheat breeding.

Characterization of agronomic and quality traits and HSW-G5 compositions from the progenies of common wheat (Triticum aestivum L.) with different protein content.

High molecular weight glutenin subunits (HMW-GS) play an essential role in wheat processing quality. In this study, we evaluated the genetic pattern with HMW-GS composition between generations and examined whether agronomic and quality traits were correlated with each other. A wheat (Triticum aestivum L.) cultivar with high protein content and 2 cultivars with low protein content were subjected to a reciprocal cross. Sixteen agronomic and 4 quality characteristics were investigated. A total of 216 seeds from each F2 generation were chosen randomly and analyzed for HMW-GS composition using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Agronomic and quality characteristics were not significantly different between reciprocal crosses, indicating no cytoplasmic effect on the characteristics studied. The separation ratio of 2 HMW-GS loci was 9:3:3:1, indicating no linkage between any 2 loci. The novel HMW-GS N was detected in cultivar R145, which did not follow the Mendelian segregation ratio. A Glu-A1a(1) band was not detected in 1 individual from Tian8901xR145. Average grain weight per spike was significantly correlated with quality characteristics and may be a suitable criterion for selecting high protein content in wheat breeding programs.

Effect of high molecular weight glutenin subunit composition in common wheat on dough properties and steamed bread quality

Steamed bread is a popular staple food in Asia with different flour quality requirements from pan bread. Little is known about how glutenin characteristics affect steamed bread quality. This work investigated how deletions of high-molecular-weight glutenin subunits (HMW-GS) influence gluten properties and Chinese steamed bread quality using 16 wheat lines grown in Texas. Although similar in protein content (134-140 mg g⁻¹), gluten composition and dough properties differed widely among the lines. Compared with non-deletion lines, deletion lines had lower (P < 0.05) unextractable polymeric protein (294 vs 470 mg g⁻¹), HMW-GS/low-molecular-weight glutenin subunit ratio (0.25 vs 0.41), dough force to extend (0.16 vs 0.44 N) and mixing peak time (2.03 vs 4.52 min). Deletion lines with HMW-GS composition of 2*/17+_/5+_ and 2*/17+_/2+12 showed moderate gluten strength (mixing peak time, 1.96-2.94 min; force to extend, 0.18-0.23 N) and high dough extensibility (106-129 mm). These lines also produced good steamed bread quality (score, 60.8-65.0) with good elasticity and crumb structure. Deletion at Glu-B1y and/or Glu-D1y loci in high-strength hard wheat produced good dough properties for steamed bread. This suggests that wheat functionality for steamed bread can be improved by manipulating HMW-GS composition.

Quality trait variations in [60Co]-irradiated wheat and high-molecular-weight glutenin subunit mutant identification

With 300 Gy of [(60)Co] γ-ray radiation of dry wheat seeds of Vortex 9722, the protein content, wet gluten content, sedimentation value, and hardness variation were analyzed in 341 lines in M4. Using over population mean ± 2X standard deviation as the screening standard, 8 lines with higher protein and wet gluten content and 4 lines with lower protein and wet gluten content were selected. In the M5 generation, the quality traits - silty parameters and high molecular weight glutenin subunits (HMW-GS) - were further analyzed in these 12 lines. The results showed that in the M5 generation, the quality traits in some variants were significantly different from those in the parents; the farinograms varied greatly. Eleven variants had significantly different HMW-GS bands compared to their parents. The parents had a HMW-GS composition of 5 + 14 + 15 + 12 + 9, and the variants had HMW-GS of 11 + 5 + 7 + 9 + 12 subunits or 1 + 5 + 7 + 8 + 12 subunits, indicating that the glutenin loci of these lines were mutated.