The wheat sucrose synthase gene TaSus1 is a determinant of grain number per spike

Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The effects of TaSus1 on grain number per spike(GNS)also are largely unknown.Our previous genome-wide association study identified TaSus-A1 as a candidate gene controlling fertile spikelet number per spike(FSN).In the present study,we generated two independent mutants for the three TaSus1 homoeologs by CRISPR/Cas9-mediated genome editing.The triple mutants displayed lower FSN,GNS,grain number per spikelet(GNST),and TGW than wild-type plants.In 306 hexaploid wheat accessions,two single-nucleotide polymorphisms in TaSus-A1 contributed differently to GNS.Introgression of the two alleles into a wheat genetic background confirmed their effects.The alleles differed in geographical distribution among the accessions.

Characterization of a 4.1 Mb inversion harboring the stripe rust resistance gene YR86 on wheat chromosome 2AL

Wheat cultivar Zhongmai 895 was earlier found to carry YR86 in an 11.6 Mb recombination-suppressed region on chromosome 2AL when crossed with Yangmai 16.To fine-map the YR86 locus,we developed two large F2 populations from crosses Emai 580/Zhongmai 895 and Avocet S/Zhongmai 895.Remarkably,both populations exhibited suppressed recombination in the same 2AL region.Collinearity analysis across Chinese Spring,Aikang 58,and 10+wheat genomes revealed a 4.1 Mb chromosomal inversion spanning 708.5-712.6 Mb in the Chinese Spring reference genome.Molecular markers were developed in the breakpoint and were used to assess a wheat cultivar panel,revealing that Chinese Spring,Zhongmai 895,and Jimai 22 shared a common sequence named InvCS,whereas Aikang 58,Yangmai 16,Emai 580,and Avocet S shared the sequence named InvAK58.The inverted configuration explained the suppressed recombination observed in all three bi-parental populations.Normal recombination was observed in a Jimai 22/Zhongmai 895 F2 population,facilitating mapping of YR86 to a genetic interval of 0.15 cM corresponding to 710.27-712.56 Mb falling within the inverted region.Thirty-three high-confidence genes were annotated in the interval using the Chinese Spring reference genome,with six identified as potential candidates for YR86 based on genome and transcriptome analyses.These results will accelerate map-based cloning of YR86 and its deployment in wheat breeding.

Breeding wheat for resistance to Fusarium head blight in the Global North: China, USA, and Canada

The objective of this paper is to review progress made in wheat breeding for Fusarium head blight(FHB) resistance in China, the United States of America(USA), and Canada. In China,numerous Chinese landraces possessing high levels of FHB resistance were grown before the 1950 s. Later, pyramiding multiple sources of FHB resistance from introduced germplasm such as Mentana and Funo and locally adapted cultivars played a key role in combining satisfactory FHB resistance and high yield potential in commercial cultivars.Sumai 3, a Chinese spring wheat cultivar, became a major source of FHB resistance in the USA and Canada, and contributed to the release of more than 20 modern cultivars used for wheat production, including the leading hard spring wheat cultivars Alsen, Glenn, Barlow and SY Ingmar from North Dakota, Faller and Prosper from Minnesota, and AAC Brandon from Canada. Brazilian wheat cultivar Frontana, T. dicoccoides and other local germplasm provided additional sources of resistance. The FHB resistant cultivars mostly relied on stepwise accumulation of favorable alleles of both genes for FHB resistance and high yield,with marker-assisted selection being a valuable complement to phenotypic selection. With the Chinese Spring reference genome decoded and resistance gene Fhb1 now cloned, new genomic tools such as genomic selection and gene editing will be available to breeders, thus opening new possibilities for development of FHB resistant cultivars.

Development of image-based wheat spike counter through a Faster R-CNN algorithm and application for genetic studies

Spike number(SN) per unit area is one of the major determinants of grain yield in wheat. Development of high-throughput techniques to count SN from large populations enables rapid and cost-effective selection and facilitates genetic studies. In the present study, we used a deep-learning algorithm, i.e., Faster Region-based Convolutional Neural Networks(Faster R-CNN) on Red-Green-Blue(RGB) images to explore the possibility of image-based detection of SN and its application to identify the loci underlying SN. A doubled haploid population of 101 lines derived from the Yangmai 16/Zhongmai 895 cross was grown at two sites for SN phenotyping and genotyped using the high-density wheat 660 K SNP array.Analysis of manual spike number(MSN) in the field, image-based spike number(ISN), and verification of spike number(VSN) by Faster R-CNN revealed significant variation(P < 0.001) among genotypes, with high heritability ranged from 0.71 to 0.96. The coefficients of determination(R^(2)) between ISN and VSN was 0.83, which was higher than that between ISN and MSN(R^(2)= 0.51), and between VSN and MSN(R^(2)= 0.50). Results showed that VSN data can effectively predict wheat spikes with an average accuracy of 86.7% when validated using MSN data. Three QTL Qsnyz.caas-4 DS, Qsnyz.caas-7 DS, and QSnyz.caas-7 DL were identified based on MSN, ISN and VSN data, while QSnyz.caas-7 DS was detected in all the three data sets. These results indicate that using Faster R-CNN model for image-based identification of SN per unit area is a precise and rapid phenotyping method, which can be used for genetic studies of SN in wheat.

Dissecting conserved cis-regulatory modules of Glu-1 promoters which confer the highly active endosperm-specific expression via stable wheat transformation

Wheat high-molecular-weight glutenin subunits(HMW-GS) determine dough elasticity and play an essential role in processing quality. HMW-GS are encoded by Glu-1 genes and controlled primarily at transcriptional level, implemented through the interactions between cis-acting elements and trans-acting factors. However, transcriptional mechanism of Glu-1 genes remains elusive. Here we made a comprehensive analysis of cis-regulatory elements within 1-kb upstream of the Glu-1 start codon(-1000 to-1) and identified 30 conserved motifs. Based on motif distribution pattern, three conserved cis-regulatory modules(CCRMs), CCRM1(-300 to-101), CCRM2(-650 to-400), and CCRM3(-950 to-750), were defined, and their functions were characterized in wheat stable transgenic lines transformed with progressive 5′ deletion promoter::GUS fusion constructs. GUS staining, qP CR and enzyme activity assays indicated that CCRM2 and CCRM3 could enhance the expression level of Glu-1, whereas the 300-bp promoter(-300 to-1), spanning CCRM1 and core region(-100 to-1), was enough to ensure accurate Glu-1 initiation at 7 days after flowering(DAF) and shape its spatiotemporal expression pattern during seed development. Further transgenic assays demonstrated that CCRM1-2(-300 to-209) containing Complete HMW Enhancer(-246 to-209) was important for expression level but had no effect on expression specificity in the endosperm. In contrast, CCRM1-1(-208 to-101) was critical for both expression specificity and level of Glu-1. Our findings not only provide new insights to uncover Glu-1 transcription regulatory machinery but also lay foundations for modifying Glu-1 expression.

Genome-wide association mapping of vitamins B1 and B2 in common wheat

Vitamin B is essential for maintaining normal life activities in humans and animals who have to intake the microelement from the outside, especially from cereal products. In the present study 166 Chinese and foreign wheat cultivars planted in two environments were characterized for variation in vitamin B1 and B2 contents. A genome-wide association study(GWAS) using the wheat 90 K SNP assay identified 17 loci for vitamin B1 and 7 for vitamin B2 contents. Linear regression analysis showed a significantly positive correlation of the number of favorable alleles with vitamin B1 and B2 contents. Marker-trait associations(MTAs) at IWB43809(6AS, 0cM) and IWB69903(6AS, 13cM) were new and stable, and significantly associated with vitamin B1 content across two environments. The loci identified in this study and associated SNP markers could be used for improvement of vitamin B1 and B2 contents to obtain superior quality along with grain yield in wheat.

Identification of cancer patients using claims data from health insurance systems: A real-world comparative study

Objective: To evaluate the accuracy of identifying cancer patients by use of medical claims data in a health insurance system in China, and provide the basis for establishing the claims-based cancer surveillance system in China.Methods: We chose Hua County, Henan Province as the study site, and randomly selected 300 and 1,200 qualified inpatient electronic medical records(EMRs) as well as the New Rural Cooperative Medical Scheme(NCMS) claims records for cancer patients in Hua County People’s Hospital(HCPH) and Anyang Cancer Hospital(ACH) in 2017. Diagnostic information for NCMS claims was evaluated on an individual level, and sensitivity and positive predictive value(PPV) were calculated taking the EMRs as the gold standard.Results: The sensitivity of NCMS was 95.2%(93.8%-96.3%) and 92.0%(88.3%-94.8%) in ACH and HCPH,respectively. The PPV of the NCMS was 97.8%(96.7%-98.5%) in ACH and 89.0%(84.9%-92.3%) in HCPH.Overall, the weighted and combined sensitivity and PPV of NCMS in Hua County was 93.1% and 92.1%,respectively. Significantly higher sensitivity and PPV in identifying patients with common cancers than noncommon cancers were detected in HCPH and ACH separately(P<0.01).Conclusions: Identification of cancer patients by use of the NCMS is accurate on individual level, and it is therefore feasible to conduct claims-based cancer surveillance in areas not covered by cancer registries in China.

Identification of QTL for adult-plant resistance to powdery mildew in Chinese wheat landrace Pingyuan 50

Powdery mildew caused by Blumeria graminis f. sp. tritici is one of the major wheat diseases worldwide. The Chinese wheat landrace Pingyuan 50 has shown adult-plant resistance(APR)to powdery mildew in the field for over 60 years. To dissect the genetic basis of APR to powdery mildew in this cultivar, a mapping population of 137 double haploid(DH) lines derived from Pingyuan 50/Mingxian 169 was evaluated in replicated field trials for two years in Beijing(2009–2010 and 2010–2011) and one year in Anyang(2009–2010). A total of 540 polymorphic SSR markers were genotyped on the entire population for construction of a linkage map and QTL analysis. Three QTL were mapped on chromosomes 2BS(QPm.caas-2BS.2), 3BS(QPm.caas-3BS),and 5AL(QPm.caas-5AL) with the resistance alleles contributed by Pingyuan 50 explaining 5.3%,10.2%, and 9.1% of the phenotypic variances, respectively, and one QTL on chromosome 3BL(QPm.caas-3BL) derived from Mingxian 169 accounting for 18.1% of the phenotypic variance.QPm.caas-3BS, QPm.caas-3BL, and QPm.caas-5AL appear to be new powdery mildew APR loci.QPm.caas-2BS.2 and QPm.caas-5AL are possibly pleiotropic or closely linked resistance loci to stripe rust resistance QTL. Pingyuan 50 could be a potential genetic resource to facilitate breeding for improved APR to both powdery mildew and stripe rust.

Health-related quality of life among rural residents aged 45-69 years in Hua County, Henan Province, China： Results of ESECC Trial for esophageal cancer screening with endoscopy

Objective： There have been few population-based studies evaluating health related quality of life（HRQOL） in rural populations in China, and this study aimed to assess the current status of and risk factors for HRQOL in a general rural population in high risk region of esophageal cancer in China.Methods： From November 2015 to September 2016, 12,085 permanent residents aged 45–69 years from 257 villages in the Endoscopic Screening for Esophageal Cancer in China（ESECC） trial（Clinical Trials.gov：NCT01688908） randomly selected from Hua County, Henan Province, China were interviewed. The EQ-5 D-3 L,a generic measure of HRQOL, and a questionnaire were used to assess their HRQOL and potential risk factors.Results： Among all the participants, 30.62% of the participants reported problems in at least one EQ-5 D dimension. Pain/discomfort（25.52%） was the most frequently reported problem followed by anxiety/depression（7.97%）, mobility（5.82%）, usual activities（2.61%） and self-care（1%）. These rural residents had a mean EQ-5 D index score of 0.948, and lower EQ-5 D index scores were associated with older age, female gender, lower levels of household annual per capita income, living alone, using shallow wells as main source of drinking water, exposure to family members smoking, testiness, unhealthy dietary habits, overweight or obesity, upper gastrointestinal cancer related symptoms and chronic diseases.Conclusions： Rural residents in China have a relatively low quality of life. Health promotion programs in this population should focus on the elderly, especially elderly women and the elderly living alone. Improving basic living circumstances and primary medical care services should be priorities. Results of this study will also serve as the basis for the cost-utility evaluation in our ESECC screening trial.

QTL mapping of starch granule size in common wheat using recombinant inbred lines derived from a PH82-2/Neixiang188 cross

Starch is a crucial component determining the processing quality of wheat(Triticum aestivum L.)-based products. Wheat starch generally contains A-type and B-type starch granules, having different effects on starch properties and end-use qualities. In the present study, 240 recombinant inbred lines(RILs) derived from a PH82-2/Neixiang 188 cross were grown in Anyang, Henan, China, during three cropping seasons. A-type and B-type granule contents were determined using a laser diffraction particle size analyzer, defined as the percentage of total starch volume. A total of 195 SSR and STS markers were used to construct a genetic map. QTL analysis was performed by composite interval mapping. Three QTL for A-type starch granule content were mapped on chromosomes 1DL, 7BL and 4AL, explaining5.6%, 5.2% and 3.8% of the phenotypic variation, respectively. These results provide useful information for improving starch quality in common wheat.

QTL mapping of adult plant resistance to stripe rust and leaf rust in a Fuyu 3/Zhengzhou 5389 wheat population

Stripe or yellow rust(YR)and leaf rust(LR)cause large losses in wheat production worldwide.Resistant cultivars curtail the levels of losses.The present study aimed to identify quantitative trait loci(QTL)for YR and LR resistance in 147 F2:6 recombinant inbred lines(RIL)derived from the cross Fuyu 3/Zhengzhou 5389.The RIL population and parents were genotyped with the Wheat55 K single nucleotide polymorphism(SNP)array and simple sequence repeat(SSR)markers.All materials were also phenotyped for YR severity at Mianyang in Sichuan province and Baoding in Hebei province in the 2015/2016,2016/2017,and 2017/2018 cropping seasons,and LR severity at Zhoukou in Henan province and at Baoding in 2017/2018.Eleven QTL for YR resistance and five for LR resistance were detected using inclusive composite interval mapping(Ici Mapping).Four of these QTL on chromosomes 1 BL,2 BS,3 AL,and 5 AL conferred resistance to both YR and LR.The QTL on 1 BL was Lr46/Yr29,and that on 7 BL might be Lr68.The QTL on chromosome 2 BS was detected at a similar position to previously detected loci.QYr.hebau-3 AL/QLr.hebau-3 AL,QYr.hebau-5 AL/QLr.hebau-5 AL,QYr.hebau-7 DL,QYr.hebau-4 BS,QYr.hebau-6 DL,and QYr.hebau-2 AS are likely to be new.An SSR marker for QYr.hebau-7 DL was developed and validated in a diverse wheat panel from China,suggesting effectiveness in different genetic backgrounds.These QTL with closely linked SNP and SSR markers could be useful for marker-assisted selection in wheat breeding programs targeting durable resistance to both diseases.

In silico curation of QTL-rich clusters and candidate gene identification for plant height of bread wheat

Many genetic loci for wheat plant height(PH) have been reported, and 26 dwarfing genes have been catalogued. To identify major and stable genetic loci for PH, here we thoroughly summarized these functionally or genetic verified dwarfing loci from QTL linkage analysis and genome-wide association study published from 2003 to 2022. A total of 332 QTL, 270 GWAS loci and 83 genes for PH were integrated onto chromosomes according to their locations in the IWGSC RefSeq v2.1 and 65 QTL-rich clusters(QRC) were defined. Candidate genes in each QRC were predicted based on IWGSC Annotation v2.1 and the information on functional validation of homologous genes in other species. A total of 38 candidate genes were predicted for 65 QRC including three GA2ox genes in QRC-4B-IV, QRC-5A-VIII and QRC-6A-II(Rht24) as well as GA 20-oxidase 2(TaSD1-3A) in QRC-3A-IV. These outcomes lay concrete foundations for mapbased cloning of wheat dwarfing genes and application in breeding.

Identification and validation of stable quantitative trait loci for yield component traits in wheat

Grain weight and grain number are important yield component traits in wheat and identification of underlying genetic loci is helpful for improving yield.Here,we identified eight stable quantitative trait loci(QTL)for yield component traits,including five loci for thousand grain weight(TGW)and three for grain number per spike(GNS)in a recombinant inbred line population derived from cross Yangxiaomai/Zhongyou 9507 across four environments.Since grain size is a major determinant of grain weight,we also mapped QTL for grain length(GL)and grain width(GW).QTGW.caas-2D,QTGW.caas-3B,QTGW.caas-5A and QTGW.caas-7A.2 for TGW co-located with those for grain size.QTGW.caas-2D also had a consistent genetic position with QGNS.caas-2D,suggesting that the pleiotropic locus is a modulator of trade-off effect between TGW and GNS.Sequencing and linkage mapping showed that TaGL3-5A and WAPO-A1 were candidate genes of QTGW.caas-5A and QTGW.caas-7A.2,respectively.We developed Kompetitive allele specific PCR(KASP)markers linked with the stable QTL for yield component traits and validated their genetic effects in a diverse panel of wheat cultivars from the Huang-Huai River Valley region.KASP-based genotyping analysis further revealed that the superior alleles of all stable QTL for TGW but not GNS were subject to positive selection,indicating that yield improvement in the region largely depends on increased TGW.Comparative analyses with previous studies showed that most of the QTL could be detected in different genetic backgrounds,and QTGW.caas-7A.1 is likely a new QTL.These findings provide not only valuable genetic information for yield improvement but also useful tools for marker-assisted selection.

QTL mapping for pre-harvest sprouting in a recombinant inbred line population of elite wheat varieties Zhongmai 578 and Jimai 22

Pre-harvest sprouting(PHS)is one of the serious global issues in wheat production.Identification of quantitative trait loci(QTL)and closely-linked markers is greatly helpful for wheat improvement.In the present study,a recombinant inbred line(RIL)population derived from the cross of Zhongmai 578(ZM578)/Jimai 22(JM22)and parents were phenotyped in five environments and genotyped by the wheat 50 K single-nucleotide polymorphism(SNP)array.Two QTL of germination index(GI),QGI.caas-3A and QGI.caas-5A,were detected,explaining 4.33%–5.58%and 4.43%–8.02%of the phenotypic variances,respectively.The resistant effect of QGI.caas-3A was contributed by JM22,whereas that of QGI.caas.5A was from ZM578.The two QTL did not correspond to any previously identified genes or genetic loci for PHSrelated traits according to their locations in the Chinese Spring reference genome,indicating that they are likely to be new loci for PHS resistance.Four kompetitive allele-specific PCR(KASP)markers K_AX-109605367and K_AX-179559687 flanking QGI.caas-3A,and K_AX-111258240 and K_AX-109402944flanking QGI.caas-5A,were developed and validated in a natural population of 100 wheat cultivars.The distribution frequency of resistance alleles at Qphs.caas-3A and Qphs.caas-5A loci were 82.7%and57.1%,respectively,in the natural population.These findings provide new QTL and tightly linked KASP markers for improvement of PHS resistance in wheat.

Precision screening for esophageal squamous cell carcinoma in China

Esophageal squamous cell carcinoma(ESCC)is the predominant subtype of esophageal cancer in China,and this neoplasm is associated with high morbidity and mortality as well as clear geographical heterogeneity.Since primary prevention for ESCC lacks a clear intervention target,secondary prevention,also known as screening and early diagnosis and early treatment,has become the mainstay of ESCC prevention and control in China.ESCC screening in China has been subject to decades of evaluation and practice.However,the ESCC screening strategy currently adopted in China has encountered a developmental bottleneck.In this review,we have summarized studies and significant findings for ESCC screening and proposed advancement of screening strategies as follows:1)evidence from randomized controlled trials is needed to support the effectiveness and health economic value of endoscopic screening for ESCC;2)the current traditional screening and surveillance strategies warrant reform,and a risk-prediction-based precision strategy should be established;and 3)a deeper understanding of the value of opportunistic screening in the prevention and control of ESCC in China is called for.Due to the low absolute prevalence of precancerous lesions,substantial investment of resources and nonnegligible risks of invasive screening techniques,precision and individualization should be the main direction of cancer screening programs for the future.We advocate cooperation on the part of Chinese scientists to solve this major China-specific health problem in the next decades.

Development and validation of a questionnaire-based risk scoring system to identify individuals at high risk for gastric cancer in Chinese populations

Objective:This study aimed to develop and validate a risk scoring system to identify high-risk individuals carrying malignant lesions in stomach for tailored gastric cancer screening.Methods:A gastric cancer risk scoring system(GC-RSS)was developed based on questionnaire-based predictors for gastric cancer derived from systematic literature review.To assess the capability of this system for discrimination,risk scores for 8,214 and 7,235 outpatient subjects accepting endoscopic examination in two endoscopy centers,and 32,630 participants in a community-based cohort in China were calculated to plot receiver operating characteristic curves and generate area under the curve(AUC).To evaluate the performance of GC-RSS,the screening proportion,sensitivity and detection rate ratio compared to universal screening were used under different risk score cutoff values.Results:GC-RSS comprised nine predictors including advanced age,male gender,low body mass index(<18.5 kg/m^(2)),family history of gastric cancer,cigarette smoking,consumption of alcohol,preference for salty food,irregularity of meals and consumption of preserved food.This tool performed well in determining the risk of malignant gastric lesions with AUCs of 0.763,0.706 and 0.696 in three validation sets.When subjects with risk scores≥5 were evaluated with endoscopy,nearly 50%of these endoscopies could be saved with a detection rate of over 1.5 times achieved.When the cutoff was set at 8,only about 10%of subjects with the highest risk would be offered endoscopy,and detection rates for gastric cancer could be increased 2-4 fold compared to universal screening.Conclusions:An effective questionnaire-based GC-RSS was developed and validated.This tool may play an important role in establishing a tailored screening strategy for gastric cancer in China.

Oral microbiome and risk of malignant esophageal lesions in a high-risk area of China:A nested case-control study

Objective:We aimed to prospectively evaluate the association of oral microbiome with malignant esophageal lesions and its predictive potential as a biomarker of risk.Methods:We conducted a case-control study nested within a population-based cohort with up to 8 visits of oral swab collection for each subject over an 11-year period in a high-risk area for esophageal cancer in China.The oral microbiome was evaluated with 16 S ribosomal RNA(rRNA)gene sequencing in 428 pre-diagnostic oral specimens from 84 cases with esophageal lesions of severe squamous dysplasia and above(SDA)and 168 matched healthy controls.DESeq analysis was performed to identify taxa of differential abundance.Differential oral species together with subject characteristics were evaluated for their potential in predicting SDA risk by constructing conditional logistic regression models.Results:A total of 125 taxa including 37 named species showed significantly different abundance between SDA cases and controls(all P<0.05&false discovery rate-adjusted Q<0.10).A multivariate logistic model including 11 SDA lesion-related species and family history of esophageal cancer provided an area under the receiver operating characteristic curve(AUC)of 0.89(95%CI,0.84-0.93).Cross-validation and sensitivity analysis,excluding cases diagnosed within 1 year of collection of the baseline specimen and their matched controls,or restriction to screenendoscopic-detected or clinically diagnosed case-control triads,or using only bacterial data measured at the baseline,yielded AUCs>0.84.Conclusions:The oral microbiome may play an etiological and predictive role in esophageal cancer,and it holds promise as a non-invasive early warning biomarker for risk stratification for esophageal cancer screening programs.

Challenge and future of cancer screening in China: Insights from esophageal cancer screening practice

Cancer stands as a prominent public health concern in China, with elusive intervention targets due to unidentified high-risk causal factors for most cancers. Consequently, emphasis has shifted towards screening, diagnosing, and treating early cancer cases within the general population. However, China faces considerable obstacles in its cancer prevention and control efforts, attributing to the complexity and heterogeneity of the occurrence, progression, and prognosis of malignant tumors across populations, time, and regions. Taking esophageal cancer screening practices as an example, this review outlines the importance and assessment of cancer screening, delineating major challenges in China's cancer prevention and control: 1) limited comprehension of cancer's natural history;2) lack of “China Evidence” supporting screening effectiveness and value;3) compromised efficiency and accuracy in current screening modality;and 4) insufficient sustainability of the current screening practices and translation of relevant scientific research achievements. To address these challenges, we propose potential coping strategies: 1)establishing tailored technologies and pathways for cancer prevention and control based on population-based and clinical epidemiological studies using high-quality designs;2) breaking conventional constraints to establish a novel cancer screening strategy aligned with real-world needs;and 3) establishing enhanced communication platforms among scientific research teams, policymakers, and industrial institutions to foster collaboration and innovation.

Dynamic metabolite QTL analyses provide novel biochemical insights into kernel development and nutritional quality improvement in common wheat

Despite recent advances in crop metabolomics,the genetic control and molecular basis of the wheat kernel metabolome at different developmental stages remain largely unknown.Here,we performed widely tar-geted metabolite profiling of kernels from three developmental stages(grain-filling kernels[FKs],mature kernels[MKs],and germinating kernels[GKs])using a population of 159 recombinant inbred lines.We de-tected 625 annotated metabolites and mapped 3173,3143,and 2644 metabolite quantitative trait loci(mQTLs)in FKs,MKs,and GKs,respectively.Only 52 mQTLs were mapped at all three stages,indicating the high stage specificity of the wheat kernel metabolome.Four candidate genes were functionally vali-dated by in vitro enzymatic reactions and/or transgenic approaches in wheat,three of which mediated the tricin metabolic pathway.Metaboliteflux efficiencies within the tricin pathway were evaluated,and su-perior candidate haplotypes were identified,comprehensively delineating the tricin metabolism pathway in wheat.Finally,additional wheat metabolic pathways were re-constructed by updating them to incorporate the 177 candidate genes identified in this study.Our work provides new information on variations in the wheat kernel metabolome and important molecular resources for improvement of wheat nutritional quality.

Orchestrating seed storage protein and starch accumulation toward overcoming yield–quality trade-off in cereal crops

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.