Strong Gluten Wheat Research Articles

Quantitative assessment of the effects of rising temperature on the grain protein of winter wheat in china and its adaptive strategies

With advancements in genetics and technology, wheat yields have continuously increased, but grain quality has remained stagnant or even decreased in recent decades. The effects of temperature on the future grain quality of winter wheat in China are unknown. This study used an improved WheatGrow model, along with two future temperature scenarios, to quantify the regional impacts of temperature increases on grain protein in China and aimed to find effective strategies to adapt to the impact of temperature increases on quality. Compared with those in the baseline period, the protein concentration of wheat grains in the main winter wheat production region of China increased by 0.27% and 0.41% under the 1.5 ℃ and 2.0 ℃ temperature increase scenarios, respectively. However, the grain protein concentrations in the Sichuan Basin of Medium and Weak Gluten Wheat Subregion (Ⅴ) decreased. The temperature rise was estimated to increase the proportion of strong gluten-type wheat but reduce the proportion of medium gluten-type wheat, with the proportion of weak gluten-type wheat changing slightly. Advanced planting date was projected to increase the grain protein concentration in the Northern Strong Gluten Wheat Subregion (Ⅰ), the Northern of Huang-Huai Strong and Medium Gluten Wheat Subregion (Ⅱ), the Southern of Huang-Huai Medium Gluten Wheat Subregion (Ⅲ) and the Yangzi River of Medium and Weak Gluten Wheat Subregion (Ⅳ), whereas a delayed planting date reduced the protein concentration in subregions Ⅰ, Ⅱ, and Ⅲ. In addition, the grain protein concentration was not significantly affected in the higher high-temperature threshold varieties in the southern winter wheat production region under the global warming scenarios. However, if more strong gluten-type wheat is required in the northern China in the future, varieties with lower high-temperature thresholds can be selected without considering wheat yields. Moreover, increasing the nitrogen fertilizer application rate could further increase the wheat protein concentration under future warming scenarios, and the protein concentration of wheat was more sensitive to the nitrogen fertilizer application rate in the northern winter wheat production region than in the southern region. These findings are crucial for improving grain quality across different wheat production regions of China in the future.

Quantitative proteomic analysis for characterization of protein components related to dough quality and celiac disease in wheat flour, dough, and heat-treated dough

High-sensitivity 4D label-free proteomic technology was used to identify protein components related to gluten quality and celiac disease (CD) in strong-gluten wheat cultivar KX 3302 and medium-gluten wheat cultivar BN 207. The highly expressed storage protein components in KX3302 were high-molecular-weight-glutenin-subunits (HMW-GSs), α-gliadin, and globulin, whereas those in BN207 were γ-gliadin, low-molecular-weight-glutenin-subunits (LMW-GSs) and avenin-like proteins. In addition, BN207 had more upregulated metabolic proteins than KX3302. The abundance of storage proteins increased during dough formation. After heat treatment, the upregulated proteins accounted for 57.53 % of the total proteins, but the downregulated storage proteins accounted for 79.34 % of the total storage proteins. In cultivar KX3302, CD proteins mainly included α-gliadin and HMW-GSs, whereas in BN207, they were mainly γ-gliadin and LMW-GSs. Thermal treatment significantly reduces the expression levels of CD-related proteins. These findings provide a new perspective on reducing the content of CD-related proteins in wheat products.

Optimizing Nitrogen Application for Enhanced Yield and Quality of Strong-Gluten Wheat: A Case Study of Zhongmai 578 in the North China Plain

This study was designed to determine the optimal nitrogen application rate for strong-gluten wheat cultivation in the North China Plain. Employing Zhongmai 578, a strong-gluten wheat variety, a field experiment was conducted with the following four nitrogen levels: 0 kg/ha (N0), 150 kg/ha (N1), 210 kg/ha (N2), and 270 kg/ha (N3). The research focused on examining the impact of nitrogen application on the photosynthesis, yield, and quality of strong-gluten wheat. The findings revealed that the N2 treatment (210 kg/ha) yielded the highest results compared to the N0 treatment. Photosynthetic parameters, including chlorophyll content in wheat flag leaves, generally exhibited an increase followed by a decrease, peaking at 7 days after anthesis (except for the transpiration rate, which peaked at 14 days post-anthesis). In the first year, quality indices such as water absorption, capacity, sedimentation value, ductility, protein, and wet gluten initially increased and then decreased with rising nitrogen levels. Conversely, in the second year, these quality indices, including hardness, showed a progressive increase with elevated nitrogen application. These results indicate that enhanced nitrogen application can significantly improve the photosynthetic characteristics of strong-gluten wheat, thereby augmenting both yield and quality. Within the parameters of this experiment, an application of 210 kg/ha of nitrogen emerged as the optimal rate, promoting the superior yield and quality of strong-gluten wheat in the North China Plain.

Classification of wheat grain varieties using terahertz spectroscopy and convolutional neural network

Wheat quality and quantity differ in diverse climates. Therefore, it is essential to identify the variety before purchasing and warehousing. In this study, a study on variety discrimination for 12 wheat varieties (strong-gluten wheat, medium-gluten wheat, weak-gluten wheat) using the Terahertz time-domain spectroscopy (THz-TDS) technology in combination with a Convolutional neural network (CNN). Firstly, the original Time-domain spectra (TDS) of wheat in the range of 0.1–2.0 THz were acquired, and the Frequency domain spectra (FDS), the absorption coefficient spectra in the range of 0.2–1.0 THz were obtained through Fourier Transform. Then, Competitive adaptive reweighted sampling (CARS) algorithms were applied to screen the feature spectrum. Finally, the Support vector machine (SVM), the Least square support vector machine (LS-SVM), the Back-propagation neural networks (BPNN) and CNN models were constructed using feature spectral data. By comparing the four models, it was found that the calibration set accuracy and prediction set accuracy of the CNN model reached 98.7% and 97.8% respectively, with an error recognition rate of only 2.2%. The research results show that combining THz-TDS technology with CNN has the advantages of accurate recognition and high efficiency. It can identify different wheat varieties and can be used for seed classification and quality detection.

Enhancing Wheat Gluten Content and Processing Quality: An Analysis of Drip Irrigation Nitrogen Frequency

Drip irrigation is a water-saving and fertilizer-saving application technology used in recent years, with which the frequency of drip irrigation nitrogen application has not yet been determined. In order to investigate the effects of different drip irrigation nitrogen application frequencies on the processing quality of medium-gluten wheat (Jimai22) and strong-gluten wheat (Jimai20 and Shiluan02-1), a two-year field experiment was carried out. Two frequencies of water and N application were set under the same conditions of total N application (210 kg·ha−1) and total irrigation (120 mm): DIF4, consisting of four equal applications of water and N (each of 30 kg·ha−1 of N application and 30 mm of irrigation) and DIF2, consisting of two equal applications of water and N (each of 60 kg·ha−1 of N application and 60 mm of irrigation). The results showed that IF4 significantly increased protein content by 2–8.6%, wet gluten content by 4.5–22.1%, and hardness value (p > 0.05), and PC2 was considered as a protein factor; the sedimentation value was highly significantly correlated with most of the parameters of the flour stretch (p < 0.01). DIF4 improved the stretching quality, and the flour quality of Jima22 was decreased, the flour quality of strong-gluten wheats Jimai20 and Shiluan02-1 was improved, and PC1 was considered to be the dough factor. In conclusion, although the frequency of nitrogen application by drip irrigation increased the protein factor and improved the tensile quality, the flour quality was not necessarily enhanced.

Improving of noodle quality caused by starch-protein interaction of waxy and strong-gluten wheat flour

Waxy wheat flour (WWF) has good processing properties and can be used to enhance the quality of noodles because of its high amylopectin or low amylose content. The aim of this study was to investigate the correlation between changes in the structural characteristics of waxy wheat starch (WS) and gluten (WG) and changes in noodle quality following molecular interactions with strong-gluten wheat starch (NS) and gluten (NG) by separation and reconstitution methods. The results showed that the noodle quality was better when WWF was added at 15% (w/w). WS promoted the formation of strong crystalline structure of amylopectin, and WG promoted the formation of double-helical short-range molecular structure of starch, and its degree of order was positively correlated with the cohesiveness and water absorption of cooked noodles, and negatively correlated with chewiness. The interaction of WS and WG with NS and NG could improve noodle quality through the change of intermolecular interactions.

Effects of Drip Irrigation and Fertilization Frequency on Yield, Water and Nitrogen Use Efficiency of Medium and Strong Gluten Wheat in the Huang-Huai-Hai Plain of China

Drip irrigation can reduce water and fertilizer use; however, the frequency of topdressing required for drip irrigation for wheat in the Huang-Huai-Hai region is still unclear. Through two continuous wheat season field experiments, yield related traits under traditional surface irrigation (border irrigation) and three drip fertilization frequencies (DF2, DF3, DF4, that was, topdressing water and fertilizer twice, three or four times in the same way during the growth period) of three wheat cultivars (Jimai 22, Jimai 20, Shiluan 02-1) were studied. Increasing the frequency of drip irrigation fertilization could prolong the time of high-level photosynthesis, increase the dry matter distribution amount (DMDA) of stems and leaves, and add the weight of 1000 grains; it could increase the DMDA and nitrogen distribution amount (NDA) of the stems, leaves, and grains of Jimai 22, forming higher harvest index (HI) and nitrogen harvest index (NHI), but could reduce the DMDA of the grains of Jimai 20 and Shiluan 02-1, increasing NDA, reducing the harvest index but forming a higher nitrogen harvest index. The increase in drip irrigation fertilization frequency can improve protein content, increase grain number per spike, decrease spike number, improve the yield of medium gluten wheat, and improve nitrogen partial productivity and water use efficiency, while strong gluten wheat has a decrease in yield, nitrogen partial productivity, and water use efficiency. In summary, medium gluten wheat is more suitable for higher fertilization frequency in the Huang-Huai-Hai wheat region, while strong gluten wheat is the opposite.

Cost-effective duplex Kompetitive Allele Specific PCR markers for homologous genes facilitating wheat breeding

BackgroundOwing to successful cloning of wheat functional genes in recent years, more traits can be selected by diagnostic markers, and consequently, effective molecular markers will be powerful tools in wheat breeding programs.ResultsThe present study proposed a cost-effective duplex Kompetitive Allele Specific PCR (dKASP) marker system that combined multiplex PCR and KASP™ technology to yield twice the efficiency at half the cost compared with the common KASP™ markers and provide great assistance in breeding selection. Three dKASP markers for the major genes controlling plant height (Rht-B1/Rht-D1), grain hardness (Pina-D1/Pinb-D1), and high-molecular-weight glutenin subunits (Glu-A1/Glu-D1) were successfully developed and applied in approved wheat varieties growing in the middle and lower reaches of the Yangtze River and advanced lines from our breeding program. Three markers were used to test six loci with high efficiency. In the approved wheat varieties, Rht-B1b was the most important dwarfing allele, and the number of accessions carrying Pinb-D1b was much greater than that of the accessions carrying Pina-D1b. Moreover, the number of accessions carrying favorable alleles for weak-gluten wheat (Null/Dx2) was much greater than that of the accessions carrying favorable alleles for strong-gluten wheat (Ax1 or Ax2*/Dx5). In the advanced lines, Rht-B1b and Pinb-D1b showed a significant increase compared with the approved varieties, and the strong-gluten (Ax1 or Ax2*/Dx5) and weak-gluten (Null/Dx2) types also increased.ConclusionA cost-effective dKASP marker system that combined multiplex PCR and KASP™ technology was proposed to achieve double the efficiency at half the cost compared with the common KASP™ markers. Three dKASP markers for the major genes controlling PH (Rht-B1/Rht-D1), GH (Pina-D1/Pinb-D1), and HMW-GS (Glu-A1/Glu-D1) were successfully developed, which would greatly improve the efficiency of marker-assisted selection of wheat.

Mitigating the Effect of Climate Change within the Cereal Sector: Improving Rheological and Baking Properties of Strong Gluten Wheat Doughs by Blending with Specialty Grains.

Due to the effect of climate change, wheat flour qualities with extremely high dough extensibility or dough strength are becoming more common, which impairs the production of selected wheat products such as pastries. The aim of this study was to investigate the effect of sorghum, millet, amaranth, or buckwheat addition to such a strong gluten common wheat flour (Triticum aestivum) on its rheological and baking properties. Raw materials were analyzed chemically (ash, protein, fat, starch, total dietary fiber) and physically (water absorption index, water solubility index, and pasting properties). Selected rheological analyses (Farinograph® and Extensograph®) were carried out on wheat blends, including up to 30% alternative grains. The baking properties of the blends were evaluated on standard bread and sweet milk bread recipes. Results showed that low amounts (5%) of sorghum and millet improved the dough stability of the high-gluten wheat flour. For optimum dough extensibility, additions of 30% sorghum, 15% millet, or 20% amaranth were needed. The use of gluten-free grains increased bread volume and decreased crumb firmness of the sweet milk breads when added at lower levels (5-15%, depending on the grain). In conclusion, cereal blending is a supportive tool to mitigate the effects of ongoing climate change and can enhance biodiversity and nutrition.

Response Characteristics of Growth Properties and Yield of Strong-gluten Winter Wheat Upon the Water-saving Supply Condition

Identification of the wheat cultivars with excellent strong-gluten property and the related stress resistance-associated physiological mechanism can provide practical basis for guiding the high-quality wheat cultivation under water-saving conditions. With an aim to understand the growth characteristics and yield traits of strong-gluten wheat in Hebei plain, this study investigated the photosynthetic characteristics, contents of osmotic regulatory substances (proline and soluble sugar), nitrogen uptake and accumulation, population characteristics and yield of strong-gluten wheat varieties (Gaoyou 5218, Shiyou 20 and Shishi Luan 02-1), three ones with demonstration potential, in response to reduction of water supply (irrigated prior to seed sowing and joint stage over the whole growth period). Results showed that compared with control (a common-gluten type cultivar Shimai 22), the photosynthetic parameters (chlorophyll content and Pn and gs), proline and soluble sugar contents, plant biomass, and the yield traits (grain number per spike, 1000 grain weight, and yield) were alleviated to different degrees. In contrast, the plant nitrogen content, population stem numbers, and spike amounts per planting unit area were shown to be superior to the control. According to the physiological parameters, population plant growth traits, yield and protein yield, the tested strong-gluten wheat cultivars were ranked in an order of Gaoyou 5218, Shiyou 20, and Shiluan 02-1, with the first one displaying the best on behaviors of photosynthetic parameters, osmotic regulation substance content and yield and to be similar to those shown in the control cultivar. Moreover, the grain protein yield of Gaoyou 5218 plants was higher than that of the control. Regression analysis showed that the expression level of <SUP>Δ</SUP>1-pyrrolin-5-carboxylate synthase (P5CS) gene <i>TaP5CS1</i> was highly positively correlated with the proline content of the tested varieties during growth stages, and the transcript abundance of nitrate transporter gene <i>TaNRT2.1</i> was significantly positively correlated with the nitrogen accumulative amount of plants during the same growth period. These results indicated that above genes played an important role in regulating the osmotic regulation ability and nitrogen uptake and accumulation of the strong-gluten and control cultivars under water-saving cultivation conditions. Gaoyou 5218 showed relatively elite yield and protein yield per unit area, indicating that this cultivar has an important application prospective for strong-gluten wheat cultivation.

Effects of Nitrogen Application Strategy on Nitrogen Enzyme Activities and Protein Content in Spring Wheat Grain

The aim of this study was to determine the regulatory effect of different nitrogen (N) fertilizer application rates on the grain N metabolism enzymes and protein content of drip-irrigated spring wheat under the climatic conditions in Xinjiang, China. A split plot experiment was conducted with strong gluten wheat Xinchun 38 (XC 38) and medium gluten wheat Xinchun 49 (XC 49) as experimental materials. We set up seven nitrogen treatments, in amounts of 300 (Nck), 285 (N5), 270 (N10), 255 (N15), 240 (N20), 225 (N25) and 0 (N0) kg hm−2. The effects of N application rate on nitrate reductase (NR), glutamine synthetase (GS), glutamate-pyruvate aminotransferase (GPT), protein content, protein composition, and yield of wheat grain were studied. The results showed that NR, GS, GPT, protein content, albumin, globulin, glutenin, gliadin, and yield first increased and then decreased with the decrease in N application. Furthermore, different responses to different applications between different wheat varieties was also observed. The indexes of XC 38 reached the maximum in the N15 treatment, and the yield increased 2.99~81.45%. XC 49 showed the best indicators under the N25 treatment and the yield increased 0.37~71.29%. Under the same N level, all indicators of XC 38 were better than XC 49. Correlation analysis showed that the yield and protein yield were significantly positively correlated with NR, GS, and GPT. The interaction of N fertilizer and variety had significant effects on NR, GS, GPT, protein content, components, and yield. These results show that the protein content and yield of wheat grain can be improved by reasonably adjusting the N fertilizer application strategy.

Trehalose-induced changes in the aggregation behavior and structural properties of wheat gluten

Trehalose is widely used in the food and cosmetics industry owing to its unique stabilizing properties. In this study, we aimed to further understand the effect of trehalose on the aggregation and structural properties of gluten. We investigated changes in the aggregation and textural properties, molecular weight distribution, disulfide bond contents, secondary structure, and network structure for weak-, middle-, and strong-gluten when supplemented with trehalose. The results showed that the macromolecular aggregation of gluten proteins was impaired. The hardness, gumminess, and chewiness of dough reduced, whereas adhesiveness increased significantly. Moreover, a looser gluten network structure was obtained with increase in trehalose content. High levels of trehalose (<5%) caused a decrease in the disulfide bond content. Secondary structure analysis of gluten indicated that the α-helix content increased for weak-gluten. In strong-gluten wheat, the β-sheet content was converted to random coil. This suggests that trehalose affected the hydration level of gluten. Trehalose likely competes with gluten for the available water by disrupting the hydrogen bonds between gluten and water molecules and breaking the ‘‘loop and train” model of gluten. Thus, the decreased disulfide bond content and increased α-helix and random coil contents induced by trehalose inhibited gluten aggregation and interrupted the gluten network. The study findings improve our understanding of trehalose functionality in dough of different gluten strength. Furthermore, these data provide valuable insights into the application of trehalose in wheat flour food products.

Integrated transcriptomic and metabolomic analyses revealed the regulatory mechanism of sulfur application in grain yield and protein content in wheat (Triticum aestivum L.).

Sulfur fertilizers play an important role in increasing the yield and improving the dough quality of bread wheat, but their regulatory mechanism remains unclear. In this study, 0 kg·ha−1 (S0) and 60 kg·ha−1 (S60) of sulfur were applied on the anthesis date; subsequently, immature wheat grains at 8, 13, and 18 days post-anthesis (DPA) were subjected to integrated transcriptomic and metabolomic analyses to investigate the changes in the gene/metabolite activity in a typical strong-gluten wheat, Gaoyou2018 (GY2018). Our data show that the S60 treatment could significantly increase the grain yield and grain protein content by 13.2 and 3.6%, respectively. The transcriptomic analysis revealed that 10,694 differentially expressed genes (DEGs) were induced by S60 from 8 to 18 DPA when compared with their corresponding no-sulfur controls, and most DEGs were mainly involved in lipid metabolism and amino acid metabolism pathways. Ninety-seven MYB transcription factors (TFs) were identified as responsive to the S60 treatment; of these, 66 showed significantly differential expression at 13 DPA, and MYB118 might participate in the process of sulfur metabolism by regulating glucosinolate synthesis. In total, 542 significantly enriched differentially expressed (DE) metabolites (DEMs) were identified following the S60 treatment, which mainly included secondary metabolites, carbohydrates, and amino acids. Several metabolites (e.g., glutathione, sucrose, GDP-alpha-D-glucose, and amino acids) exhibited altered abundances following the S60 treatment. The combination of transcriptomic and metabolomic analyses highlighted the important role of amino acid metabolism (especially cysteine, methionine, and glutathione metabolism) and starch and sucrose metabolism pathways after S60 application. Our results provide valuable information enhancing our understanding of the molecular mechanism of the response to sulfur and provide useful clues for grain protein quality formation and yield improvement in bread wheat.

Establishment and Application of Multiplex PCR Systems Based on Molecular Markers for HMW-GSs in Wheat

High-molecular-weight glutenin subunits (HMW-GSs) encoded by alleles at the Glu-A1, Glu-B1, and Glu-D1 loci confer unique end-use quality properties of common wheat (Triticum aestivum L.). Wheat accessions with the high-quality HMW-GSs combination of Ax2*/Bx7OE/Dx5 usually exhibit strong gluten characteristics. In order to stack these three high-quality subunit genes by molecular markers in strong gluten wheat breeding, an agarose gel-based multiplex PCR marker for these high-quality HMW-GSs and two agarose gel-based multiplex PCR markers detecting the homozygosity of Ax2* and Bx7OE subunits were developed. These markers were verified in an F2 segregating population from a cross between a medium-gluten winter wheat cultivar with the HMW-GSs combination of Ax null/Bx7 + By8/Dx4 + Dy12 and a strong-gluten spring wheat cultivar with the HMW-GSs combination of Ax2*/Bx7OE + By8*/Dx5 + Dy10. By integrating the newly established multiplex PCR markers and a published co-dominant PCR marker of the Dx5 subunit, a complete molecular marker selection system was established. After multiple rounds of molecular marker-assisted selection with the system, 17 homozygous winter wheat lines that stacked the three high-quality HMW-GSs were generated. The gluten strength of these homozygous lines was comparable to their strong-gluten parent, but significantly higher than that of their medium-gluten parent by measuring their lactic acid-sodium dodecyl sulfate solvent retention capacities of whole wheat meal. The multiplex PCR systems established in the present study can be used for molecular marker-assisted selection of strong gluten wheats.

Molecular cloning and sequence analysis of 1Dx-type HMW-GS genes from different wheat varieties

AbstractHigh-molecular-weight glutenin subunits (HMW-GS) contribute to dough elasticity and bread baking quality in wheat. In this study, wheat varieties were classified based on their HMW-GS composition into three groups: 1Dx5 (5 + 10, Gaoyou 8901, Xinmai 28, Xinmai 19, Xinmai 26 and Jinbaoyin), 1Dx2 (2 + 12, Zhoumai 24, Xinmai 9 and Yumai) and 1Dx4 (4 + 12, Aikang 58). Sequence analysis showed that 1Dx-GY8901, 1Dx-XM28, 1Dx-XM19 and 1Dx-XM26 were similar to the 1Dx5 gene and clustered on the same branch, while 1Dx-AK58, 1Dx-ZM24, 1Dx-JBY, 1Dx-YM, 1Dx-XM9 and 1Dx-JBY were more similar to the 1Dx2 gene and clustered on the same branch with 1Dx.2.2. There was a mutation of Ser to Cys at position S2, for an extra Cys in the repeat regions of 1Dx-XM19, 1Dx-XM26, 1Dx-XM28 and 1Dx-GY8901. The wheat HMW-GS genes exhibited similar percentages of α-helix, extended strand, β-turn and random coil structure, with ranges of 13.33–13.59, 4.77–5.78, 7.08–9.18 and 72.3–73.94%, respectively. Sequence conservation and the composition of HMW-GS subunits were also analysed for a series of strong gluten wheat varieties, Xinmai 9 (1, 7 + 8, 2 + 12), Xinmai 19 (1, 7 + 9, 5 + 10), Xinmai 26 (1, 7 + 8, 5 + 10) and Xinmai 28 (1, 7 + 9, 5 + 10). The results of this work should facilitate future breeding efforts and provide the theoretical basis for wheat quality improvement.

Effects of wide range sowing on grain yield, quality, and nitrogen use of strong gluten wheat

<p id="C3">It is well known that wide range sowing can simultaneously improve grain yield (GY) and nitrogen use efficiency (NUE). However, the effects of wide range sowing on grain quality have not been investigated while GY and NUE increased. In the present study, four winter wheat cultivars (Gaoyou 5766, Jimai 44, Taishan 27, and Zhouyuan 9369) were used as experimental materials and two sowing patterns (the wide range sowing and conventional drilling sowing) were designed during 2018-2019 and 2019-2020 growing seasons. Also, we investigated the effects of wide range sowing on GY, NUE, and grain quality. Under wide range sowing, grain number on unit land area were increased by an average of 13.16% across cultivars and growth seasons mainly due to the increase of spike number on unit land area, and in turn GY increased by an average of 13.39%. Meanwhile, nitrogen (N) uptake during whole growth season especially at post-anthesis stage were enhanced. The N accumulation during whole growth season increased by an average of 10.29% while that increased by an average of 36.83% at post-anthesis stage. Consequently, N uptake efficiency and NUE increased by 12.73% and 13.39%, respectively. Enhanced N uptake resulted in a sufficient N supply for grain and a significant increase in grain N accumulation on unit land area. A similar increase magnitude was observed between grain N accumulation (on average 13.38%), grain number (13.16%), and GY (13.39%). As a result, total quantity of N per grain and grain protein concentration remained unchanged, which led to a stable grain protein composition and grain quality. Conclusively, wide range sowing can maintain good grain quality with increased GY and NUE by optimizing coupling of GY formation process with the process of N uptake and translocation.

EVALUATING SPLIT TIMING FERTILIZER APPLICATIONS FOR IMPROVING BREAD BAKING QUALITY OF SOFT RED WINTER WHEAT IN KENTUCKY

There is growing interest among farmers to locally produce high protein and strong gluten wheat that is suitable for bread making and meet the demand of local artisanal bakers in Kentucky. The warm and humid weather in southeast region is ideal for soft red winter wheat (SRW) production which characterized by low protein content. The technique of splitting nitrogen (N) fertilization according to the growth stages has been suggested to improve protein content and its composition. This study evaluated the effect of split N application on yield and baking quality traits of two SRW wheat cultivars grown in the eastern U.S. region in conventional and organic cropping systems. One landrace (Purple Straw) and one modern cultivar (Pembroke 2014 ) were grown under three split N application treatments (ST1, ST2 and ST3). Late N applications (ST3) significantly increased protein content for both years by 5.45% and 6.11% respectively compared to a single application; however, this treatment decreased yield. Cropping system had consistent effects in that conventional system exceeded organic system except for thousand kernel weight. Conventional system had greater yield by 16.11% and 20.17% respectively for both years than organic system. Similarly, sedimentation value (a baking quality trait) was greater by 14.27% and 11.12% respectively in conventional than organic system. This study has generally found improvement in protein content by N application on soft red winter wheat. In addition, more studies should be done in organic system to examine other baking quality traits.

Laccase‐induced wheat bran arabinoxylan hydrogels from different wheat cultivars: Structural, physicochemical, and rheological characteristics

The impact of three arabinoxylan (AX) cultivars (262, 44, 229) on the physicochemical, rheological, and microstructural characteristics of AX hydrogels was explored. The gelation of AX262 was faster and the viscoelastic modulus was higher. During the gelation process, the consumption of ferulic acids was 96%, 87%, and 69% for AX262, AX44, and AX229, respectively, indicating a higher oxidative cross-linking degree of AX262. The decline of adsorption intensity for AX262 hydrogel at 1,644 and 3,423 cm−1 was more pronounced, which might be related to a denser gel network as a result of higher oxidation degree of FA. Meanwhile, AX262 hydrogel was more capable of binding water molecules and exhibited better thermal stability. The difference in the gelation properties of varied AX cultivars lied in the molecular structure. AX262 had a higher ferulic acid content (0.23 μg/mg) and larger molecular weight with 1.17 × 106 Da, contributing to an enhanced oxidative cross-linking capacity. Novelty impact statement Wheat bran arabinoxylans extracted from strong gluten wheat cultivars with higher contents of FA were suitable to fabricate hydrogel system, due to their better oxidative cross-linking capacity. The prepared AX hydrogel had uniform honeycomb structure with enhanced thermal stability and mechanical properties, which could be potentially used as delivery system for bioactive compounds.

Aggregative and structural properties of wheat gluten during post-harvest maturation

Wheat post-harvest maturation induced baking and technological quality improvement through a series of biochemical and colloidal changes. Weak-, middle-, and strong-gluten wheat displayed varying gluten network structures that determined the flour ingredient formulations and processing conditions. However, the aggregation and structural properties of wheat with different gluten strengths post-harvest remain largely unexplored. In this study, we investigated changes in the aggregative properties of gluten protein, gluten composition, S–S content, network structure, and secondary structures of weak-, middle-, and strong-gluten wheat during post-harvest maturation. The results indicated that the macromolecular aggregation of gluten proteins was impaired in weak-gluten wheat, while it was enhanced for middle- and strong-gluten wheat during storage. Post-harvest maturation resulted in an increase in glutenin content and a decline in the gliadin and gliadin/glutenin ratio in middle- and strong-gluten wheat as well as a decreased glutenin content in weak-gluten wheat. Moreover, additional gluten subunits were observed in middle- and strong-gluten wheat, but no substantial change was observed in weak-gluten wheat with long storage times. The disulfide bond content of gluten protein for middle-gluten and strong-gluten gradually increased but declined for weak-gluten wheat. Secondary structure analysis of gluten indicated that post-harvest maturation caused the conversion of α-helix to random coil for weak-gluten wheat, β-turn and random coil to α-helix for middle-gluten wheat, and β-turns to α-helix for strong-gluten wheat, which led to a disordered structure for weak gluten and an ordered stable gluten network for middle- and strong-gluten. Thus, the increased S–S and α-helix content induced by post-harvest maturation enhanced the aggregation of gluten proteins for middle- and strong-gluten wheat, resulting in a denser network structure. Conversely, the decrease in the content of α-helix resulted in the existence of a looser gluten network structure for weak-gluten wheat during post-harvest maturation.

Promoter DNA hypermethylation of TaGli-γ-2.1 positively regulates gluten strength in bread wheat

IntroductionGliadins are the major components of gluten proteins with vital roles on properties of end-use wheat product and health-relate quality of wheat. However, the function and regulation mechanisms of γ-gliadin genes remain unclear. ObjectivesDissect the effect of DNA methylation in the promoter of γ-gliadin gene on its expression level and gluten strength of wheat. MethodsThe prokaryotic expression and reduction–oxidation reactions were performed to identify the effect of TaGli-γ-2.1 on dough strength. Bisulfite analysis and 5-Aza-2′-deoxycytidine treatment were used to verify the regulation of TaGli-γ-2.1 expression by pTaGli-γ-2.1 methylation. The content of gluten proteins composition was measured by RP-HPLC, and the gluten strength was measured by Gluten Index and Farinograph. ResultsTaGli-γ-2.1 was classified into a subgroup of γ-gliadin multigene family and was preferentially expressed in the later period of grain filling. Addition of TaGli-γ-2.1 protein fragment into strong gluten wheat flour significantly decreased the stability time. Hypermethylation of three CG loci of pTaGli-γ-2.1 conferred to lower TaGli-γ-2.1 expression. Treatment with 5-Aza-2′-deoxycytidine in seeds of strong gluten wheat varieties increased the expression levels of TaGli-γ-2.1. Furthermore, the accumulations of gliadin and γ-gliadin were significantly decreased in hypermethylated wheat varieties, corresponding with the increasing of gluten index and dough stability time. ConclusionEpigenetic modification of pTaGli-γ-2.1 affected gluten strength by modulating the proportion of gluten proteins. Hypermethylation of pTaGli-γ-2.1 is a novel genetic resource for enhancing gluten strength in wheat quality breeding.