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Background and Objectives: This study explored the impact of nitrogen (N) application on yield and breadmaking as well as arabinoxylan (AX) content of wheat varieties Zhongmai 578 and Jimai 22 across varied environments, aiming to optimize N levels for improved outcomes. Findings: Significant N effects were observed on yield, flour properties, and breadmaking quality traits. Both varieties displayed high yield potential and stability, with Zhongmai 578 excelling in thousand kernel weight and Jimai 22 in spike number. Optimal N rates varied by location, with some achieving peak yields at reduced N levels. Processing traits like dough properties and bread‐making quality were influenced by E × N interactions. Arabinoxylans profiles was not affected by different N input. Conclusions: Customizing N applications to specific environment is critical for maximizing wheat yield potential and quality. Environmental considerations are integral for achieving desired processing traits and yield, highlighting the need for tailored N strategies in wheat cultivation. Significance and Novelty: This study emphasizes the importance of site‐specific optimization of N levels for enhanced yield and processing quality. It offers novel insights into site‐specific N management, showcasing its relevance in modern agricultural practices for sustainable crop production. [ABSTRACT FROM AUTHOR]

Drought is one of the most adverse factors affecting plant growth and productivity. Identifying elite genotypes and their ideotypic traits conferring high yield potential and drought tolerance is critical in selecting and breeding drought‐tolerant wheat cultivars. In this study, we conducted field experiments at the Xinxiang Agricultural Comprehensive Experimental station in the North China Plain from 2018 to 2020 and assessed 209 wheat cultivars released since the 1940s under irrigated and nonirrigated conditions. Then, we selected drought‐tolerant cultivars by classifying them into four groups based on yield response to drought stress and several drought indices. Finally, the key ideotypic traits associated with high yield potential and drought tolerance were identified. Results indicated that the grain yield of the 209 cultivars decreased on average by 10.4% and 9.4% under nonirrigated treatment in 2018–2019 and 2019–2020, respectively, relative to full irrigation. The high‐yielding cultivars under both irrigation treatments are characterised by a compact plant type, larger thousand‐grain weight, larger chlorophyll content, higher leaf photosynthesis, shorter plant height and stay‐green traits. The stomatal and nonstomatal limitations are strongly associated with genotype yield performance, elucidating a potential mechanism underlying drought tolerance. Drought tolerance and yield stability of wheat cultivars have been improved through breeding over the past 70 years. Our findings enhance understanding of drought tolerance and identify genotypes and traits beneficial for breeding high‐yielding and drought‐tolerant cultivars. [ABSTRACT FROM AUTHOR]

Summary: Although forward‐genetics‐metabolomics methods such as mGWAS and mQTL have proven effective in providing myriad loci affecting metabolite contents, they are somehow constrained by their respective constitutional flaws such as the hidden population structure for GWAS and insufficient recombinant rate for QTL. Here, the combination of mGWAS and mQTL was performed, conveying an improved statistical power to investigate the flavonoid pathways in common wheat. A total of 941 and 289 loci were, respectively, generated from mGWAS and mQTL, within which 13 of them were co‐mapped using both approaches. Subsequently, the mGWAS or mQTL outputs alone and their combination were, respectively, utilized to delineate the metabolic routes. Using this approach, we identified two MYB transcription factor encoding genes and five structural genes, and the flavonoid pathway in wheat was accordingly updated. Moreover, we have discovered some rare‐activity‐exhibiting flavonoid glycosyl‐ and methyl‐transferases, which may possess unique biological significance, and harnessing these novel catalytic capabilities provides potentially new breeding directions. Collectively, we propose our survey illustrates that the forward‐genetics‐metabolomics approaches including multiple populations with high density markers could be more frequently applied for delineating metabolic pathways in common wheat, which will ultimately contribute to metabolomics‐assisted wheat crop improvement. [ABSTRACT FROM AUTHOR]

Summary: Wheat needs different durations of vernalization, which accelerates flowering by exposure to cold temperature, to ensure reproductive development at the optimum time, as that is critical for adaptability and high yield. TaVRN1 is the central flowering regulator in the vernalization pathway and encodes a MADS‐box transcription factor (TF) that usually works by forming hetero‐ or homo‐dimers. We previously identified that TaVRN1 bound to an MADS‐box TF TaSOC1 whose orthologues are flowering activators in other plants. The specific function of TaSOC1 and the biological implication of its interaction with TaVRN1 remained unknown. Here, we demonstrated that TaSOC1 was a flowering repressor in the vernalization and photoperiod pathways by overexpression and knockout assays. We confirmed the physical interaction between TaSOC1 and TaVRN1 in wheat protoplasts and in planta, and further validated their genetic interplay. A Flowering Promoting Factor 1‐like gene TaFPF1‐2B was identified as a common downstream target of TaSOC1 and TaVRN1 through transcriptome and chromatin immunoprecipitation analyses. TaSOC1 competed with TaVRT2, another MADS‐box flowering regulator, to bind to TaVRN1; their coding genes synergistically control TaFPF1‐2B expression and flowering initiation in response to photoperiod and low temperature. We identified major haplotypes of TaSOC1 and found that TaSOC1‐Hap1 conferred earlier flowering than TaSOC1‐Hap2 and had been subjected to positive selection in wheat breeding. We also revealed that wheat SOC1 family members were important domestication loci and expanded by tandem and segmental duplication events. These findings offer new insights into the regulatory mechanism underlying flowering control along with useful genetic resources for wheat improvement. [ABSTRACT FROM AUTHOR]

Achieving high yield and good quality in crops is essential for human food security and health. However, there is usually disharmony between yield and quality. Seed storage protein (SSP) and starch, the predominant components in cereal grains, determine yield and quality, and their coupled synthesis causes a yield–quality trade‐off. Therefore, dissection of the underlying regulatory mechanism facilitates simultaneous improvement of yield and quality. Here, we summarize current findings about the synergistic molecular machinery underpinning SSP and starch synthesis in the leading staple cereal crops, including maize, rice and wheat. We further evaluate the functional conservation and differentiation of key regulators and specify feasible research approaches to identify additional regulators and expand insights. We also present major strategies to leverage resultant information for simultaneous improvement of yield and quality by molecular breeding. Finally, future perspectives on major challenges are proposed. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to evaluate the impact of Lugol‐unstained lesion (LUL) location on the detection yield, which may help the endoscopist select targets for biopsy. Methods: We enrolled 1064 subjects who had LULs at the baseline screening of a population‐based randomized controlled trial. There were 1166 LULs with recorded location and pathologic diagnosis, and these were used for analysis. The detection rate of severe dysplasia and above (SDA) was calculated as the number of LULs identified as SDA divided by the number of LULs biopsied. Logistic regression with a generalized estimating equation was applied to evaluate the association between the location of a given LUL and the risk of the LUL being SDA. Results: The detection rate of SDA for LULs located in the lower, middle, and upper esophagus increased from 5.9% and 10.9% to 16.7%. LUL location was significantly associated with having SDA (adjusted odds ratio (OR)upper vs. lower = 2.88, 95% confidential interval (CI) = 1.48–5.60; adjusted ORmiddle vs. lower = 1.63, 95% CI = 0.96–2.76), and the association was stronger in subgroups with a family history of esophageal squamous cell carcinoma (ESCC) (adjusted ORupper vs. lower = 9.72, 95% CI = 2.57–36.69; adjusted ORmiddle vs. lower = 3.76, 95% CI = 0.93–15.21). Conclusions: Our results suggest that more attention should be paid by endoscopists to LULs in the upper and middle esophagus, particularly for individuals with a family history of ESCC. [ABSTRACT FROM AUTHOR]

Sustainable wheat production is challenged by climate change events such as drought, salinity, and heat stress. Senescence is a gradual programmed cell death trait occurring post anthesis in wheat (Triticum aestivum), with significant affecting stability of yield and quality‐related traits under climate severities. Phenotyping of complex traits is increasingly perceived as a bottleneck due to elevated labor costs and time in large field conditions. Unmanned aerial vehicle (UAV)‐based platforms using RGB imagery and ground phenotyping–based novel traits can facilitate the repeated nondestructive measurements of crop canopy traits cost‐effectively. Here, we described combined application of UAV‐based RGB imaging and ground measurements based novel trait to quantify canopy senescence in wheat. We reported senescence related traits with high heritability in a recombinant inbred line population derived from the cross Zhongmai 175/Lunxuan 987. Our results showed that the selection of slow senescence genotypes using UAV‐based vegetation indices (VIs) was equally effective as ground‐based traits and illustrated significant variations among the genotypes. We also identified five quantitative trait loci (QTL) for canopy senescence in both UAV and ground‐based datasets using a 50K single‐nucleotide polymorphism array. QTL for UAV‐based VIs from RGB imaging and ground measurements based traits were mapped on chromosomes 1B, 2B, 3A, and 4B. The integration of both datasets with genetic analysis identified an important slow senescence/stay‐green related locus on chromosome 4B that explained phenotypic variation up to 23.07% for both UAV and ground traits at late grain‐ filling stage. Three QTL (QTL‐caas.1B, QTL‐caas.3A, and QTL‐caas.4B2) on chromosomes 1B, 3A, and 4B were also validated for slow senescence with high chlorophyll level and cool canopy temperature in a natural population of 160 lines by developing kompetitive allele‐specific PCR markers. QTL‐caas.4B1 was validated not only for senescence but also for plant height. Our findings suggest that UAV‐based RGB imagery is advantageous for precise and rapid assessment of senescence related traits and genetic studies of senescence in wheat. Core Ideas: Unmanned aerial vehicle (UAV)‐based phenotyping platforms using RGB imagery can facilitate the repeated nondestructive measurements of canopy greenness and senescence cost‐effectively.We have integrated vegetation indices derived from UAV‐based RGB pixels and ground measurements with quantitative genetic analysis to identify loci controlling canopy senescence in wheat.We have developed kompetitive allele‐specific PCR (KASP) markers based on identified loci that contribute to variations in wheat senescence. [ABSTRACT FROM AUTHOR]

Summary: High‐molecular‐weight glutenin subunits (HMW‐GS), a major component of seed storage proteins (SSP) in wheat, largely determine processing quality. HMW‐GS encoded by GLU‐1 loci are mainly controlled at the transcriptional level by interactions between cis‐elements and transcription factors (TFs). We previously identified a conserved cis‐regulatory module CCRM1‐1 as the most essential cis‐element for Glu‐1 endosperm‐specific high expression. However, the TFs targeting CCRM1‐1 remained unknown. Here, we built the first DNA pull‐down plus liquid chromatography‐mass spectrometry platform in wheat and identified 31 TFs interacting with CCRM1‐1. TaB3‐2A1 as proof of concept was confirmed to bind to CCRM1‐1 by yeast one hybrid and electrophoretic mobility shift assays. Transactivation experiments demonstrated that TaB3‐2A1 repressed CCRM1‐1‐driven transcription activity. TaB3‐2A1 overexpression significantly reduced HMW‐GS and other SSP, but enhanced starch content. Transcriptome analyses confirmed that enhanced expression of TaB3‐2A1 down‐regulated SSP genes and up‐regulated starch synthesis‐related genes, such as TaAGPL3, TaAGPS2, TaGBSSI, TaSUS1 and TaSUS5, suggesting that it is an integrator modulating the balance of carbon and nitrogen metabolism. TaB3‐2A1 also had significant effects on agronomic traits, including heading date, plant height and grain weight. We identified two major haplotypes of TaB3‐2A1 and found that TaB3‐2A1‐Hap1 conferred lower seed protein content, but higher starch content, plant height and grain weight than TaB3‐2A1‐Hap2 and was subjected to positive selection in a panel of elite wheat cultivars. These findings provide a high‐efficiency tool to detect TFs binding to targeted promoters, considerable gene resources for dissecting regulatory mechanisms underlying Glu‐1 expression, and a useful gene for wheat improvement. [ABSTRACT FROM AUTHOR]

Background: Current guidelines recommend only severe dysplasia and above (SDA) lesions of the esophageal squamous epithelium for clinical intervention. However, the histopathologic diagnosis derived from tissue biopsies may be subject to underestimation of severity. Methods: 1073 participants from whom biopsies were taken at baseline chromoendoscopic examination in a population‐based screening trial were enrolled in this study. The size of the Lugol‐unstained lesions (LULs) was mainly analyzed. The outcome was defined as SDA lesions either identified at baseline screening, or during follow‐up, collectively referred to as the cumulative risk of SDA. Multivariable logistic regression models were used to evaluate the cumulative risk of SDA. Results: One hundred and forty‐six SDA cases were identified in the study period. Participants with large LULs had a high cumulative incidence of SDA (cumulative incidence16–20mm: 55.88%; cumulative incidence>20mm: 76.92%) in the median of 7‐year duration. LULs of large size were significantly associated with a higher cumulative risk of SDA, regardless of the pathologic diagnosis (adjusted OR16–20mmvs.≤5mm = 21.02, 95% CI: 7.56–58.47; adjusted OR>20mmvs.≤5mm = 33.62, 95% CI: 11.79–95.87). Conclusions: Results from this study suggest physician–patient shared decision‐making regarding clinical treatment or intensive surveillance should be carried out for LULs >20 mm in the esophagus, regardless of the histologic diagnosis. For those with LULs of 16–20 mm, intensive surveillance would also best be considered. [ABSTRACT FROM AUTHOR]

Powdery mildew is a very destructive disease that threatens yield and quality of wheat. In the present study, 262 recombinant inbred lines derived from a cross between Zhongmai 578 (ZM578) with moderate resistance to powdery mildew and Jimai 22 (JM22) with high resistance to powdery mildew in the field were used to map powdery mildew resistance loci using the high‐density Illumina iSelect 50K single‐nucleotide polymorphism array. Three quantitative trait loci (QTLs) on chromosomes 2B, 5B, and 5D were identified by inclusive composite interval mapping, designated as QPm.caas‐2BL.1, QPm.caas‐5BL, and QPm.caas‐5DL, respectively, explaining 5.0%–37.0% of the phenotypic variances. The resistance allele of QPm.caas‐5BL was contributed by ZM578, whereas alleles of QPm.caas‐2BL.1 and QPm.caas‐5DL were from JM22. QPm.caas‐2BL.1, detected in all the six experimental environments, was a major and stable QTL. QPm.caas‐5DL was detected in five of the six environments and is likely to be a new QTL for powdery mildew resistance. The kompetitive allele‐specific PCR (KASP) markers Kpm‐2BL and Kpm‐5DL for QPm.caas‐2BL.1 and QPm.caas‐5DL, respectively, were validated in a diverse panel of 287 cultivars. These KASP markers, tightly linked with the QTLs, can be used for marker‐assisted breeding targeting the improvement of powdery mildew resistance in wheat. Core Ideas: Three major quantitative trait loci (QTLs) for powdery mildew resistance were identified in the Zhongmai 578/Jimai 22 population.QPm.caas‐5DL is likely a new QTL, with the resistance allele from Jimai 22.Two kompetitive allele‐specific PCR (KASP) markers for QPm.caas‐2BL.1 and QPm.caas‐5DL were validated in a panel of 287 wheat cultivars. [ABSTRACT FROM AUTHOR]

Melatonin (Mel) is a multifunctional biomolecule found in both animals and plants. In plants, the biosynthesis of Mel from tryptophan (Trp) has been delineated to comprise of four consecutive reactions. However, while the genes encoding these enzymes in rice are well characterized no systematic evaluation of the overall pathway has, as yet, been published for wheat. In the current study, the relative contents of six Mel‐pathway‐intermediates including Trp, tryptamine (Trm), serotonin (Ser), 5‐methoxy tryptamine (5M‐Trm), N‐acetyl serotonin (NAS) and Mel, were determined in 24 independent tissues spanning the lifetime of wheat. These studies indicated that Trp was the most abundant among the six metabolites, followed by Trm and Ser. Next, the candidate genes expressing key enzymes involved in the Mel pathway were explored by means of metabolite‐based genome‐wide association study (mGWAS), wherein two TDC genes, a T5H gene and one SNAT gene were identified as being important for the accumulation of Mel pathway metabolites. Moreover, a 463‐bp insertion within the T5H gene was discovered that may be responsible for variation in Ser content. Finally, a ASMT gene was found via sequence alignment against its rice homolog. Validations of these candidate genes were performed by in vitro enzymatic reactions using proteins purified following recombinant expression in Escherichia coli, transient gene expression in tobacco, and transgenic approaches in wheat. Our results thus provide the first comprehensive investigation into the Mel pathway metabolites, and a swift candidate gene identification via forward‐genetics strategies, in common wheat. [ABSTRACT FROM AUTHOR]

Background and Aim: The impact of the presence of multiple Lugol‐unstained lesions (LULs) in the esophagus on the risk of having severe dysplasia and above (SDA) lesions among asymptomatic individuals is unknown. Methods: We collected demographic factors, behavioral variables, and features of LULs from 1073 participants who were biopsied at baseline endoscopic screening in a population‐based screening trial, and these individuals were followed over a median time of 7 years. Outcome events were defined as SDA identified at screening, at reexamination, or during follow‐up. "Multiple LULs" were defined as ≥ 2 LULs found in the entirety of the esophagus. Multivariable logistic regression models were fitted to assess the effect of "multiple LULs" on the cumulative risk of SDA. Results: There were 147 SDA cases in the current study. After adjustment for potential risk factors and endoscopic features of LULs, the presence of "multiple LULs" slightly increased the cumulative risk of having SDA with no statistical significance (adjusted odds ratio [OR] = 1.26; 95% confidence interval [CI] [0.85, 1.88]). Further stratified analysis showed that this association was strong among subjects with small LULs (≤ 5 mm) (adjusted OR = 3.29; 95% CI [1.39, 7.79]). However, no such association was observed in subjects with larger LULs (adjusted OR = 0.99; 95% CI [0.63, 1.55], Pinteraction = 0.022). Conclusions: The presence of "multiple small LULs (≤ 5 mm)" in chromoendoscopy indicates a higher cumulative risk of having SDA in the esophagus. We recommend biopsies be taken and surveillance be maintained at a more active level in individuals with relatively small but multiple LULs. [ABSTRACT FROM AUTHOR]

Genetic markers can be linked with eco‐physiological crop models to accurately predict genotype performance and individual markers' contributions in target environments, exploring interactions between genotype and environment. Here, wheat (Triticum aestivum L.) yield was dissected into seven traits corresponding to cultivar genetic coefficients in an eco‐physiological model. Loci for these traits were discovered through the genome‐wide association studies (GWAS). The cultivar genetic coefficients were derived from the loci using multiple linear regression or random forest, building a marker‐based eco‐physiological model. It is then applied to simulate wheat yields and design virtual ideotypes. The results indicated that the loci identified through GWAS explained 46%–75% variations in cultivar genetic coefficients. Using the marker‐based model, the normalized root mean square error (nRMSE) between the simulated yield and observed yield was 13.95% by multiple linear regression and 13.62% by random forest. The nRMSE between the simulated and observed maturity dates was 1.24% by multiple linear regression and 1.11% by random forest, respectively. Structural equation modelling indicated that variations in grain yield could be well explained by cultivar genetic coefficients and phenological data. In addition, 24 pleiotropic loci in this study were detected on 15 chromosomes. More significant loci were detected by the model‐based dissection method than considering yield per se. Ideotypes were identified by higher yield and more favourable alleles of cultivar genetic traits. This study proposes a genotype‐to‐phenotype approach and demonstrates novel ideas and tools to support the effective breeding of new cultivars with high yield through pyramiding favourable alleles and designing crop ideotypes. Summary statement: This study developed a novel gene‐based eco‐physiological model by linking genetic markers with cultivar genetic parameters to support effective breeding of new cultivars through pyramiding favourable alleles, designing crop ideotypes and predicting genotype and environment interactions. [ABSTRACT FROM AUTHOR]

SUMMARY: Wheat (Triticum aestivum L.) radiation use efficiency (RUE) must be raised through crop breeding to further increase the yield potential, as the harvest index is now close to its theoretical limit. Field experiments including 209 wheat cultivars which have been widely cultivated in China since the 1940s were conducted in two growing seasons (2018–2019 and 2019–2020) to evaluate the variations of phenological, physiological, plant architectural, and yield‐related traits and their contributions to RUE and to identify limiting factors for wheat yield potential. The average annual genetic gain in grain yield was 0.60% (or 45.32 kg ha−1 year−1; R2 = 0.44, P < 0.01), mainly attributed to the gain in RUE (r = 0.85, P < 0.01). The net photosynthetic rates were positively and closely correlated with grain RUE and grain yield, suggesting source as a limiting factor to future yield gains. Thirty‐four cultivars were identified, exhibiting not only high RUE, but also traits contributing to high RUE and 11 other critical traits – of known genetic basis – as potential parents for breeding to improve yield and RUE. Our findings reveal wheat traits and the associated loci conferring RUE, which are valuable for facilitating marker‐assisted breeding to improve wheat RUE and yield potential. [ABSTRACT FROM AUTHOR]

Currently, surveillance for esophageal squamous cell carcinoma (ESCC) runs a risk of underestimation of early lesions which show absence of iodine staining, with no or only mild histologic changes. The development of molecular markers that indicate risk of progression is thus warranted. We performed whole‐exome sequencing on biopsies from two sequential endoscopies of a single esophageal lesion and matching blood samples. There were 27 pairs of age‐, gender‐, pathologic stage‐, and sampling interval‐matched progressors and non‐progressors identified in a prospective community‐based ESCC screening trial. Putative molecular progression markers for ESCC were first evaluated by comparing somatic mutation, copy number alteration (CNA), and mutational signature information among progressors and non‐progressors. These markers were then validated with another 24 pairs of matched progressors and non‐progressors from the same population using gene alteration status identified by target sequencing and quantitative PCR. Progressors had more somatic mutation and CNA burden, as well as apolipoprotein B mRNA editing catalytic polypeptide‐like and age‐related signature weights compared with non‐progressors. A gene score consisting of somatic NOTCH1 mutation and CDKN2A deletion is predictive of risk of progression in lesions which show absence of iodine staining under endoscopy but have no or only mild dysplasia. This gene score was also validated in an external cohort of matched progressors and non‐progressors. Absence of NOTCH1 mutation and presence of CDKN2A deletion are markers of progression in squamous lesions of the esophagus. This gene score would be an ideal indicator for assisting the pathologist in the identification of high‐risk individuals who could be potentially 'missed' or subject to a risk underestimation by histologic analysis, and might improve the performance of ESCC surveillance. © 2022 The Pathological Society of Great Britain and Ireland. [ABSTRACT FROM AUTHOR]

The health benefits of whole wheat consumption can be partially attributed to wheat's phytochemicals, including phenolic acids, flavonoids, alkylresorcinols, carotenoids, phytosterols, tocopherols, and tocotrienols. It is of increasing interest to produce whole wheat products that are rich in bioactive phytochemicals. This review provides the fundamentals of the chemistry, extraction, and occurrence of wheat phytochemicals and includes critical discussion of several long‐lasting issues: (1) the commonly used nomenclature on distribution of wheat phenolic acids, namely, soluble‐free, soluble‐conjugated, and insoluble‐bound phenolic acids; (2) different extraction protocols for wheat phytochemicals; and (3) the chemistry and application of in vitro antioxidant assays. This review further discusses recent advances on the effects of genotypes, environments, field management, and processing techniques including ultrafine grinding, germination, fermentation, enzymatic treatments, thermal treatments, and food processing. These results need to be interpreted with care due to varied sample preparation protocols and limitations of in vitro assays. The bioaccessibility, bioavailability, metabolism, and potential health benefits of wheat phytochemicals are also reviewed. This comprehensive and critical review will benefit scientific researchers in the field of bioactive compounds of cereal grains and also those in the cereal food industry to produce high‐quality functional foods. [ABSTRACT FROM AUTHOR]

SUMMARY: Roots are essential multifunctional plant organs involved in water and nutrient uptake, metabolite storage, anchorage, mechanical support, and interaction with the soil environment. Understanding of this 'hidden half' provides potential for manipulation of root system architecture (RSA) traits to optimize resource use efficiency and grain yield in cereal crops. Unfortunately, root traits are highly neglected in breeding due to the challenges of phenotyping, but could have large rewards if the variability in RSA traits can be fully exploited. Until now, a plethora of genes have been characterized in detail for their potential role in improving RSA. The use of forward genetics approaches to find sequence variations in genes underpinning desirable RSA would be highly beneficial. Advances in computer vision applications have allowed image‐based approaches for high‐throughput phenotyping of RSA traits that can be used by any laboratory worldwide to make progress in understanding root function and dissection of the genetics. At the same time, the frontiers of root measurement include non‐invasive methods like X‐ray computer tomography and magnetic resonance imaging that facilitate new types of temporal studies. Root physiology and ecology are further supported by spatiotemporal root simulation modeling. The discovery of component traits providing improved resilience and yield advantage in target environments is a key necessity for mainstreaming root‐based cereal breeding. The integrated use of pan‐genome resources, now available in most cereals, coupled with new in‐field phenotyping platforms has the potential for precise selection of superior genotypes with improved RSA. Significance Statement: We reviewed the current status of genetics underpinning root system architecture in cereals and presented a comprehensive genetic framework. We further provided a comparative analysis of the phenotyping methods, different root phenes and their interaction with the environment, and breeding applications. [ABSTRACT FROM AUTHOR]

Summary: Rht‐B1b and Rht‐D1b, the 'Green Revolution' (GR) genes, greatly improved yield potential of wheat under nitrogen fertilizer application, but reduced coleoptile length, seedling vigor and grain weight. Thus, mining alternative reduced plant height genes without adverse effects is urgently needed.We isolated the causal gene of Rht24 through map‐based cloning and characterized its function using transgenic, physiobiochemical and transcriptome assays. We confirmed genetic effects of the dwarfing allele Rht24b with an association analysis and also traced its origin and distribution.Rht24 encodes a gibberellin (GA) 2‐oxidase, TaGA2ox‐A9. Rht24b conferred higher expression of TaGA2ox‐A9 in stems, leading to a reduction of bioactive GA in stems but an elevation in leaves at the jointing stage. Strikingly, Rht24b reduced plant height, but had no yield penalty; it significantly increased nitrogen use efficiency, photosynthetic rate and the expression of related genes. Evolutionary analysis demonstrated that Rht24b first appeared in wild emmer and was detected in more than half of wild emmer and wheat accessions, suggesting that it underwent both natural and artificial selection.These findings uncover an important genetic resource for wheat breeding and also provide clues for dissecting the regulatory mechanisms underlying GA‐mediated morphogenesis and yield formation. [ABSTRACT FROM AUTHOR]

It is important to understand the genetic gain achieved through selection of key yield traits for planning future breeding strategies in developing high yielding wheat (Triticum aestivum L.) cultivars. The aim of this study was to characterize the genetic changes and genotype × environment (G×E) interaction by additive main effect and multiplicative interactions (AMMI) for morphological, physiological, and yield component traits under five environments using 24 wheat cultivars released from 1911 to 2016 in Pakistan. There was a significant increase in grain yield (9.03 kg ha−1 yr−1, 0.37%), and plant height was reduced linearly (−0.26 cm yr−1, −0.33%). The traits waxiness, leaf rolling, harvest index, spike length, and grains per spike significantly increased but the gain was only 0.16–0.2% per year. Analysis of variance revealed that genotype, environment, and G×E interaction were highly significant (P <.01) for all traits except relative chlorophyll content, biomass, days to maturity, and number of spikes. Gene‐specific markers identified the durable resistance gene Lr67/Yr46/Sr55/Pm46 in obsolete cultivars as early as 1911, whereas the photoperiod‐insensitive allele Ppd‐D1a and reduced height alleles Rht‐B1b and Rht‐D1b were present only in the post‐1965 cultivars. Diversity analysis based on a 50K single nucleotide polymorphism genotyping array clearly differentiated temporal patterns in 24 cultivars, which was correlated with the agronomic performance of the cultivars. This dataset provided detailed insight into the performance of historical wheat cultivars and could help in devising wheat breeding strategies to focus on the traits contributing to grain yield and have slower rate of genetic progress. Core Ideas: The genetic gain in morphology of Pakistani bread wheat cultivars over 105 yr areas was assessed.Leaf rolling, waxiness, and grains/spikes associated with genetic gains in grain yield were achieved by breeding.The performance and stability of yield and yield‐related traits was analyzed for the different cultivars. [ABSTRACT FROM AUTHOR]

SUMMARY: High‐molecular‐weight glutenin subunits (HMW‐GS) are major components of seed storage proteins (SSPs) and largely determine the processing properties of wheat (Triticum aestivum) flour. HMW‐GS are encoded by the GLU‐1 loci and regulated at the transcriptional level by interaction between cis‐elements and transcription factors (TFs). We recently validated the function of conserved cis‐regulatory modules (CCRMs) in GLU‐1 promoters, but their interacting TFs remained uncharacterized. Here we identified a CCRM‐binding NAM‐ATAF‐CUC (NAC) protein, TaNAC100, through yeast one‐hybrid (Y1H) library screening. Transactivation assays demonstrated that TaNAC100 could bind to the GLU‐1 promoters and repress their transcription activity in tobacco (Nicotiana benthamiana). Overexpression of TaNAC100 in wheat significantly reduced the contents of HMW‐GS and other SSPs as well as total seed protein. This was confirmed by transcriptome analyses. Conversely, enhanced expression of TaNAC100 increased seed starch contents and expression of key starch synthesis‐related genes, such as TaGBSS1 and TaSUS2. Y1H assays also indicated TaNAC100 binding with the promoters of TaGBSS1 and TaSUS2. These results suggest that TaNAC100 functions as a hub controlling seed protein and starch synthesis. Phenotypic analyses showed that TaNAC100 overexpression repressed plant height, increased heading date, and promoted seed size and thousand kernel weight. We also investigated sequence variations in a panel of cultivars, but did not identify significant association of TaNAC100 haplotypes with agronomic traits. The findings not only uncover a useful gene for wheat breeding but also provide an entry point to reveal the mechanism underlying metabolic balance of seed storage products. Significance Statement: High‐molecular‐weight glutenin subunits (HMW‐GS) have a great effect on wheat (Triticum aestivum) quality. Here we identified a NAC transcription factor, TaNAC100, binding with HMW‐GS promoters. TaNAC100 overexpression in wheat reduced the contents of HMW‐GS and total seed protein, but increased seed starch content. TaNAC100 overproduction also significantly affects agronomic traits. The findings not only uncover a useful gene for wheat breeding but also provide an entry point to reveal the mechanism underlying metabolic balance of seed storage products. [ABSTRACT FROM AUTHOR]

Summary: Timely flowering is essential for optimum crop reproduction and yield. To determine the best flowering‐time genes (FTGs) relevant to local adaptation and breeding, it is essential to compare the interspecific genetic architecture of flowering in response to light and temperature, the two most important environmental cues in crop breeding. However, the conservation and variations of FTGs across species lack systematic dissection. This review summarizes current knowledge on the genetic architectures underlying light and temperature‐mediated flowering initiation in Arabidopsis, rice, and temperate cereals. Extensive comparative analyses show that most FTGs are conserved, whereas functional variations in FTGs may be species specific and confer local adaptation in different species. To explore evolutionary dynamics underpinning the conservation and variations in FTGs, domestication and selection of some key FTGs are further dissected. Based on our analyses of genetic control of flowering time, a number of key issues are highlighted. Strategies for modulation of flowering behavior in crop breeding are also discussed. The resultant resources provide a wealth of reference information to uncover molecular mechanisms of flowering in plants and achieve genetic improvement in crops. [ABSTRACT FROM AUTHOR]

Summary: The marriage of metabolomic approaches with genetic design has proven a powerful tool in dissecting diversity in the metabolome and has additionally enhanced our understanding of complex traits. That said, such studies have rarely been carried out in wheat. In this study, we detected 805 metabolites from wheat kernels and profiled their relative contents among 182 wheat accessions, conducting a metabolite‐based genome‐wide association study (mGWAS) utilizing 14 646 previously described polymorphic SNP markers. A total of 1098 mGWAS associations were detected with large effects, within which 26 candidate genes were tentatively designated for 42 loci. Enzymatic assay of two candidates indicated they could catalyse glucosylation and subsequent malonylation of various flavonoids and thereby the major flavonoid decoration pathway of wheat kernel was dissected. Moreover, numerous high‐confidence genes associated with metabolite contents have been provided, as well as more subdivided metabolite networks which are yet to be explored within our data. These combined efforts presented the first step towards realizing metabolomics‐associated breeding of wheat. [ABSTRACT FROM AUTHOR]

The primary cause of time‐dependent discoloration in wheat (Triticum aestivum L.)‐based products is polyphenol oxidase (PPO) activity. A comprehensive genetic characterization of PPO activity in wheat could expedite the development of wheat varieties with low PPO activity. To dissect the genetic architecture of PPO activity in wheat flour, a panel of 166 diverse bread wheat cultivars was phenotyped in four different environments and genotyped by high‐density wheat 90K and 660K arrays. A genome‐wide association study (GWAS) was performed by a mixed linear model that incorporated population structure and relative kinship. Four hundred and sixty‐five stable marker–trait associations representative of 43 quantitative trait loci (QTL) for PPO activity identified in at least two environments were located on all wheat chromosomes except 5A, with each explaining 6.6–32.4% of the phenotypic variance. Based on IWGSC RefSeq v1.0, we found that QPPO2A.3, QPPO2B.1, QPPO2B.2, and QPPO2D.2 were consistent with the previously reported QTL, and 12 QTL located on homoeologous group 1 chromosomes (6 QTL), chromosomes 4B, 4D, and 7A (2 QTL), and chromosome 7B (2 QTL) are likely to be new PPO loci. Based on physical positions of QTL and previous studies, Ppo‐A1, Ppo‐A2, Ppo‐B2, Ppo‐D2, Pinb‐D1, and genes encoding a Cu ion‐binding protein and a Cu‐transporting ATPase RAN1‐like protein were considered as candidates for QPPO2A.3, QPPO2B.1, QPPO2D.2, QPPO5D.1, QPPO4A.2, and QPPO7D.2, respectively. This study provided insights into the molecular basis of wheat PPO activity, and associated markers can be used for selection of low PPO breeding lines as a means of improving the marketing quality of wheat products. [ABSTRACT FROM AUTHOR]

Background and objectives: Consumption of Chinese steamed bread (CSB) and noodles made from whole grain wheat flour (WWF) is encouraged due to their important nutritional elements in the outer seed layers that benefit human health. However, the use of WWF is limited because of the poor processing quality and less attractive product properties of dark color, rough texture and coarse crumb structure. Three Chinese wheat cultivars, Zhongmai 895, Yumai 49, and Zhoumai 27, were used to investigate the potentials of bran hydration and autoclaving treatments for the improvement of WWF functionality in making CSB and noodles. Findings: Bran particle size, hydration, and autoclaving treatment of WWF significantly affected the quality of dough, CSB, and noodles made from it. Farinograph water absorption and stability of WWFs with fine bran were larger than those with coarse bran. WWFs with coarse bran compared with fine bran exhibited inferior color and higher water retention capacity (WRC), and produced CSB with better texture and crumb structure and noodles with less smoothness and poor appearance. Prehydration of bran decreased dough water absorption and increased dough stability. WWFs containing bran hydrated to 40% moisture content produced CSB with the best texture and crumb structure, and the highest total score. Bran hydration merely induced negative effects on smoothness of noodles made with fine bran. Autoclaving of bran significantly improved texture and crumb structure of CSB made from WWFs with bran hydrated to 40% moisture. Autoclaved bran with 20% moisture contributed to higher total score of CSB. However, bran hydration and autoclaving resulted in darker color of noodle sheet made from WWFs. Conclusions: Hydration and autoclaving of bran could be an effective way to improve the processing quality of CSB made from WWFs, but there was little improvement in eating quality of noodles made from WWFs. Significance and novelty: This is the first research to show that hydration and autoclaving of bran could be an effective way to improve the processing quality of CSB made from WWFs. These results provide useful information for the incorporation of wheat bran to make fiber‐rich CSB. [ABSTRACT FROM AUTHOR]

Heat stress during the grain-filling stage is a major limiting factor for improving Chinese wheat production, and its effect on functional properties of flours and starches in 10 leading cultivars from the Yellow and Huai Valleys grown under normal and heat-stress environments was investigated. Heat stress during the grain-filling stage decreased total starch content but increased protein and lipid contents of wheat grains. Amylose content of wheat starch was little altered under a heat-stress environment. Heat stress did not significantly change swelling power and starch solubility of wheat starches but significantly decreased swelling power of wheat flours. Pasting viscosities of wheat starches and flours were affected differentially by heat stress. Heat stress had a significant effect on gelatinization and retrogradation properties of starches. The in vitro enzymatic digestibility of wheat starches was affected slightly by heat stress. Analysis of variance indicated that heat stress had a significant effect on some functional properties of starch and flour, although the largest source of variability in these properties was cultivar. [ABSTRACT FROM AUTHOR]

Studies of the clinical relevance of human papillomavirus (HPV) DNA load have focused mainly on HPV16 and HPV18. Data on other oncogenic types are rare. Study subjects were women enrolled in the atypical squamous cells of undetermined significance (ASC-US) and low-grade squamous intraepithelial lesion (LSIL) triage study who had ≥1 of 11 non-HPV16/18 oncogenic types detected during a 2-year follow-up at 6-month intervals. Viral load measurements were performed on the first type-specific HPV-positive specimens. The association of cervical intraepithelial neoplasia grades 2-3 (CIN2/3) with type-specific HPV DNA load was assessed with discrete-time Cox regression. Overall, the increase in the cumulative risk of CIN2/3 per 1 unit increase in log10-transformed viral load was statistically significant for four types within species 9 including HPV31 (adjusted hazard ratio [HR adjusted] = 1.32: 95% confidence interval [CI], 1.14-1.52), HPV35 (HR adjusted = 1.47; 95% CI, 1.23-1.76), HPV52 (HR adjusted = 1.14; 95% CI, 1.01-1.30) and HPV58 (HR adjusted = 1.49; 95% CI, 1.23-1.82). The association was marginally significant for HPV33 (species 9) and HPV45 (species 7) and was not appreciable for other types. The per 1 log10-unit increase in viral load of a group of species 9 non-HPV16 oncogenic types was statistically significantly associated with risk of CIN2/3 for women with a cytologic diagnosis of within normal limits, ASC-US, or LSIL at the first HPV-positive visit but not for those with high-grade SIL. Findings suggest that the viral load-associated risk of CIN2/3 is type-dependent, and mainly restricted to the species of HPV types related to HPV16, which shares this association. [ABSTRACT FROM AUTHOR]

Wheat leaf rust (LR), caused by the obligate biotrophic fungus Puccinia triticina ( Pt), is a destructive foliar disease of common wheat ( Triticum aestivum L.) worldwide. The most effective, economic means to control the disease is resistant cultivars. The Romanian wheat line Fundulea 900 showed high resistance to LR in the field. To identify the basis of resistance to LR in Fundulea 900, a population of 188 F2:3 lines from the cross Fundulea 900/'Thatcher' was phenotyped for LR severity during the 2010-2011, 2011-2012 and 2012-2013 cropping seasons in the field at Baoding, Hebei Province. Bulked segregant analysis and simple sequence repeat markers were used to identify the quantitative trait loci ( QTLs) for LR adult-plant resistance in the population. Three QTLs were detected and designated as QLr.hebau-1 BL, QLr.hebau-2 DS and QLr.hebau-7 DS. Based on the chromosome positions and molecular marker tests, QLr.hebau-1 BL is Lr46, and QLr.hebau-7 DS is Lr34. QLr.hebau-2 DS was derived from 'Thatcher' and was close to Lr22. This result suggests that Lr22b may confer residual resistance on field nurseries when challenged with isolates virulent on Lr22b, or another gene linked to Lr22b confers this resistance from 'Thatcher'. This study confirms the value of Lr34 and Lr46 in breeding for LR resistance in China; the contribution of the QTL to chromosome 2D needs further validation. [ABSTRACT FROM AUTHOR]

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We investigated alleles at 31 loci associated with adaptability, yield, and end-use quality in 107 wheat (Triticum aestivum L.) landraces (WLRs) and 121 improved historical wheat cultivars (HWCs) from Pakistan. The WLRs were categorized into two further subgroups: 36 pre-Green-Revolution landraces released as cultivars and 71 geographically spread landraces from all over Pakistan. Alleles VrnA1a, TaGW2-6A-A, TaCKX6-D1b, Pinb-D1b, Psy-A1b, and Wx-D1b were absent in WLRs, whereas ample diversity was observed at all other loci. In HWCs, only Wx-D1b and Glu-A3e were absent among the alleles tested, whereas the alleles Ppd-D1a (90%), Rht-B1b or Rht-D1b (83.4%), TaCwi-A1a (95%), TaGW2-6A-G (76%), TaCKX6-D1a (77.3%), Glu-A1b (66.1%), Glu-D1d (61.3%), Pina-D1b (88.2%), Pinb-D1a (90%), Psy-A1a (66.1%), Psy-B1b (81.8%), Psy-D1a (86.5%), Ppo-A1a (70%), TaZds-D1b (73.9%), TaLox-B1b (80.1%), and Wx-D1a (100%) predominated, indicating significant improvement in adaptability, yield potential, and end-use quality and unconscious selection for favored alleles. Higher frequencies of favored alleles at the TaCwi-A1 and TaCKX6-D1 loci influencing 1000-kernel weight (TKW) in HWCs indicated that selection pressure on these alleles during breeding successfully contributed to cultivar improvement. Wright's pairwise fixation index (Fst) statistics indicated greater genetic divergence between HWC and WLR collections (0.16) than HWC and WLR cultivars (0.14). Population structure based on functional markers (FMs) using principal component analysis partitioned the germplasm into two distinct groups. High genetic divergence and low admixture between HWCs and WLRs indicated limited use of landraces in wheat breeding in Pakistan. Our results suggested these collections as rich reservoirs of alleles and haplotype combinations that may be useful in future breeding programs. [ABSTRACT FROM AUTHOR]

The slow-rusting and mildewing gene Yr18/Lr34/Pm38/Sr57 confers partial, durable resistance to multiple fungal pathogens and has its origins in China. A number of diagnostic markers were developed for this gene based on the gene sequence, but these markers do not always predict the presence of the resistant phenotype as some wheat varieties with the gene are susceptible to stripe rust in China. We hypothesized that these varieties have a suppressor of Yr18. This study was undertaken to determine the presence of Yr18, the suppressor and/or another resistance gene in 144 Chinese wheat landraces using molecular markers and stripe rust field data. Forty-three landraces were predicted to have Yr18 based on the presence of the markers, but had final disease severities higher than 70%, indicating that this gene may be under the influence of a suppressor. Four of these landraces, 'Sichuanyonggang 2', 'Baikemai', 'Youmai' and 'Zhangsihuang', were chosen for genetic studies. Crosses were made between the lines and 'Avocet S', with further crosses of Sichuanyonggang 2 × 'Huixianhong' and Sichuanyonggang 2 × 'Chinese Spring'. The F1 plants of Sichuanyonggang 2/Chinese Spring was susceptible indicating the presence of a dominant suppressor gene. The results of genetic analyses of F2:3 and BC1F2 families derived from these crosses indicated the presence of Yr18, a Yr18 suppressor and another additive resistance gene. The Yr18 region in Sichuanyonggang 2 was sequenced to ensure that it contained the functional allele. This is the first report of a suppressor of Yr18/Lr34/Pm38/Sr57 gene with respect to stripe rust response. [ABSTRACT FROM AUTHOR]

Starch is a crucial component determining the processing quality of wheat‐based products such as Chinese steamed bread (CSB) and raw white noodles (RWN). Flour from wheat cultivar Zhongmai 175 was used for fractionation into starch, gluten, and water solubles by hand washing. The starch fraction was successfully separated into large (>10 μm diameter) and small starch granules (<10 μm diameter) by repeated sedimentation. Flour fractions were reconstituted to original levels in the flour by using constant gluten and water solubles and varying the weight ratio of large and small starch granules. As the proportion of small granules increased in the reconstituted flours, farinograph water absorption increased, and amylose content, pasting peak viscosity, trough, and final viscosity decreased. Starch granule size distribution significantly affected processing quality of CSB and RWN. Superior crumb structure score (12.0) was observed in CSB made from reconstituted flour with 35% small starch granules. CSB made from reconstituted flours with 30 and 35% small starch granules exhibited the highest total scores, with values of 85.4 and 83.3, respectively. Significant improvements in color, viscoelasticity, and smoothness of RWN were obtained with an increase in small starch granule content, and reconstituted flours with 30–40% small starch granules produced RWN with moderate firmness. [ABSTRACT FROM AUTHOR]

Variants of human papillomavirus (HPV) type 31 have been shown to be related both to risk of cervical lesions and racial composition of a population. It is largely undetermined whether variants differ in their likelihood of persistence. Study subjects were women who participated in the ASCUS-LSIL Triage Study and who had a newly detected HPV31 infection during a two-year follow-up with six-month intervals. HPV31 isolates were characterized by sequencing and assigned to one of three variant lineages. Loss of the newly detected HPV31 infection was detected in 76 (47.5%) of the 160 women (32/67 with A variants, 16/27 with B variants and 28/66 with C variants). The adjusted hazard ratio associating loss of the infection was 1.2 (95% CI, 0.7-2.1) for women with A variants and 2.1 (95% CI, 1.2-3.5) for women with B variants when compared with those with C variants. Infections with A and C variants were detected in 50 and 41 Caucasian women and in 15 and 23 African-American women, respectively. The likelihood of clearance of the infection was significantly lower in African-American women with C variants than in African-American women with A variants ( p = 0.05). There was no difference in the likelihood of clearance between A and C variants among Caucasian women. Our data indicated that infections with B variants were more likely to resolve than those with C variants. The difference in clearance of A vs. C variants in African-Americans, but not in Caucasians, suggests a possibility of the race-related influence in retaining the variant-specific infection. [ABSTRACT FROM AUTHOR]

Over the past century, environmental changes have significantly impacted wheat spike morphology, crucial for adaptation and grain yield. However, the changes in wheat spike modifications during this period remain largely unknown. This study examines 16 spike morphology traits in 830 accessions released from 1900 to 2020. It finds that spike weight, grain number per spike (GN), and thousand kernel weight have significantly increased, while spike length has no significant change. The increase in fertile spikelets is due to fewer degenerated spikelets, resulting in a higher GN. Genome‐wide association studies identified 49,994 significant SNPs, grouped into 293 genomic regions. The accumulation of favorable alleles in these genomic regions indicates the genetic basis for modification in spike morphology traits. Genetic network analysis of these genomic regions reveals the genetic basis for phenotypic correlations among spike morphology traits. The haplotypes of the identified genomic regions display obvious geographical differentiation in global accessions and environmental adaptation over the past 120 years. In summary, we reveal the genetic basis of adaptive evolution and the interactions of spike morphology, offering valuable resources for the genetic improvement of spike morphology to enhance environmental adaptation. [ABSTRACT FROM AUTHOR]