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The recently published reference genome of Aegilops tauschii provides new insights into the originator of the D genome donor of hexaploid wheat. This will be a foundation for exploring the genomic diversity underpinning adaptive traits in wheat, and ultimately advance wheat improvement efforts.

Background & Aims Chromoendoscopy with iodine staining is used to identify esophageal squamous dysplasia and esophageal squamous cell carcinomas (ESCCs)—absence of staining indicates suspicious regions of dysplasia. However, screening detects precancerous lesions (mild and moderate dysplasia) that do not require immediate treatment; it is a challenge to which lesions are at risk for progression. We investigated the association between absence of iodine staining at chromoendoscopy screening and lesion progression using 6 years of follow-up data from a population-based randomized controlled trial in China. We then constructed and validated a model to calculate risk of progression to severe dysplasia, carcinoma in situ, or ESCC. Methods We collected data from 1468 participants (45–69 years old) who were either negative for iodine staining at a baseline chromoendoscopy or found to have mild or moderate dysplasia in histologic analysis of biopsies in the Endoscopic Screening for Esophageal Cancer study in China, from January 2012 through September 2016; 788 of these participants were re-examined by endoscopy after a median interval of 4.2 years (development cohort). We investigated the association between absence of iodine staining and progression of esophageal lesions using Cox prediction models, considering corresponding baseline pathology findings and patient answers to a comprehensive questionnaire. Patients who did not receive a follow-up examination (n = 680) was used as the validation cohort; outcome events in these patients were identified by annual door to door active interviews or linkage with local electronic registry data. The primary outcome was incident esophageal severe dysplasia, carcinoma in situ, or ESCC. Results In the development cohort, 11 lesions that did not stain with iodine but were classified as not dysplastic in the histology analysis were found to be severe dysplasia, carcinoma in situ, or ESCC at the follow-up evaluation. These lesions accounted for 39.3% of all progressed lesions (n = 28). In the validation cohort, 6 patients with lesions did not stain with iodine but were classified as not dysplastic by histology had a later diagnosis of ESCC, determined from medical records; these patients accounted for 50.0% of all patients with lesion progression (n = 12) until the closing date of this study. We developed a model based on patient age, body mass index, pathology findings, and baseline iodine staining to calculate risk for severe dysplasia, carcinoma in situ, or ESCC. It identified patients for severe dysplasia, carcinoma in situ, or ESCC in the development set with an area under the curve of 0.868 (95% CI, 0.817–0.920) and in the validation set with an area under the curve of 0.850 (95% CI, 0.748–0.952). Almost no cases would be missed if subjects determined to be high or intermediate–high risk subjects by the model were included in surveillance. Conclusions Absence of iodine staining at baseline chromoendoscopy identifies esophageal lesions at risk of progression with a high level of sensitivity. A model that combines results of iodine chromoendoscopy with other patient features identifies patients at risk of lesion progression with greater accuracy than histologic analysis of baseline biopsies.

Background and Aims Prediction models for esophageal squamous cell carcinoma are not common, and no model targeting a clinical population has previously been developed and validated. We aimed to develop a prediction model for estimating the risk of high-grade esophageal lesions for application in clinical settings and to validate the performance of this model in an external population. Methods The model was developed based on the results of endoscopic evaluation of 5624 outpatients in one hospital in a high-risk region in northern China and was validated using 5765 outpatients who had undergone endoscopy in another hospital in a non-high-risk region in southern China. Predictors were selected with unconditional logistic regression analysis. The Akaike information criterion was used to determine the final structure of the model. Discrimination was estimated using the area under the receiver operating characteristic curve (AUC). Calibration was assessed using a calibration plot with an intercept and slope. Results The final prediction model contained 5 variables, including age, smoking, body mass index, dysphagia, and retrosternal pain. This model generated an AUC of 0.871 (95% confidence interval, 0.842-0.946) in the development set, with an AUC of 0.862 after bootstrapping. The 5-variable model was superior to a single age model. In the validation population, the AUC was 0.843 (95% confidence interval, 0.793-0.894). This model successfully stratified the clinical population into 3 risk groups and showed high ability for identifying concentrated groups of cases. Conclusions Our model for esophageal high-grade lesions has a high predictive value. It has the potential for application in clinical opportunistic screening to aid decision making for both health care professionals and individuals.

Figure S3. Manhattan plots for grain yield and related traits in each environment and BLUE value in the diverse panel based on SNP-GWAS. a, grain yield; b, spike number per square meter; c, kernel number per spike; d, thousand-kernel weight; e, kernel length; f, kernel width; g, spike length; h, spike dry weight; i, heading date; j, plant height; k, uppermost internode length; l, flag leaf length; m, flag leaf width; 1, 2012–2013 Anyang; 2, 2012–2013 Suixi; 3, 2013–2014 Anyang; 4, 2013–2014 Suixi; 5, 2014–2015 Anyang; 6, 2014–2015 Shijiazhuang. (DOCX 11525 kb)

Additional file 14: Figure S9. PCR profile of the Wx-B1 specific marker. M, Marker (DL2000DNA ladder; Takara Bio Company). Target fragments are shown with red arrows. Lane 1 indicates Chinese Spring; lane 2 indicates Guandong107; lane 3 and 4 show BL33 and BL31, respectively.

Table S1. Analysis of phenotypic data for grain yield and related traits in the diverse panel. (DOCX 16 kb)

Table S4. Genome coverage, physical distance and marker polymorphism. (DOCX 16 kb)

Table S3. Correlation coefficients among grain yield and related traits in the diverse panel. (DOCX 13 kb)

Table S5. Composition and lengths of blocks and haplotypes. (DOCX 14 kb)

Figure S2. Coverage of SNPs (a) and haplotypes (b) on all 21 bread wheat chromosomes. (DOCX 1094 kb)

Figure S1. Distribution of phenotypic values for grain yield and related traits in the diverse panel. GY, grain yield; SN, spike number per square meter; KNS, kernel number per spike; TKW, thousand-kernel weight; KL, kernel length; KW, kernel width; SL, spike length; SDW, spike dry weight; HD, heading date; PH, plant height; UIL, uppermost internode length; FLL, flag leaf length; FLW, flag leaf width. (DOCX 54 kb)

Table S2. Analysis of variance and broad-sense heritabilities (h2) for grain yield and related traits. (DOCX 13 kb)

The objective of this study was to establish an optimal population-level follow-up strategy for identifying incident cancers using health insurance reimbursement data in rural China.We compared active follow-up and passive linkage with claims data for identification of incident cancer cases. Claims data were derived from the New Rural Cooperative Medical Scheme (NCMS). Follow-up data from subject enrollment to December 31, 2016, regarding 33,948 subjects in a large-scale randomized controlled trial were used in this study.The overall sensitivity of passive linkage with NCMS claims data was significantly higher than that of active follow-up (95.6% vs. 54.9%, P 0.001). Of 12 cases missed by the NCMS data set, seven were treated on an outpatient basis and there were therefore no records in the NCMS system, and five were diagnosed at primary (township-level) health facilities and excluded from the quality control process. Of the 123 cases missed by active follow-up, 54 were reported as negative, 69 were reported as positive but had inaccurate information regarding the site of cancer, or exceeded the 6-month limitation from the date of diagnosis.Passive linkage with NCMS claims data is an efficient approach for identifying incident cancers in areas without cancer registries in rural China.

Wheat Avenin-like proteins (TaALP) are atypical storage proteins belonging to the Prolamin superfamily. Previous studies on ALPs have focused on the proteins’ positive effects on dough strength, whilst no correlation has been made between TaALPs and the plant immune system. Here, we performed genome-wide characterization of ALP encoding genes in bread wheat. In silico analyses indicated the presence of critical peptides in TaALPs that are active in the plant immune system. Pathogenesis-related nucleotide motifs were also identified in the putative promoter regions of TaALP encoding genes. RT-PCR was performed onTaALPand previously characterised pathogenesis resistance genes in developing wheat caryopses under control andFusarium graminearuminfection conditions. The results showed thatTaALPand NMT genes were upregulated uponF. graminearuminoculation. mRNA insitu hybridization showed thatTaALPgenes were expressed in the embryo, aleurone and sub-aleurone layer cells. SevenTaALPgenes were cloned for the expression of recombinant proteins inEscherichia coli, which displayed significant inhibitory function onF. graminearumunder anti-fungal tests. In addition, FHB index association analyses showed that allelic variations of two ALP genes on chromosome 7A were significantly correlated with FHB symptoms. Over-expression of an ALP gene on chromosome 7A showed an enhanced resistance to FHB. Yeast two Hybridization results revealed that ALPs have potential proteases inhibiting effect on metacaspases and beta-glucosidases. A vital infection process related pathogen protein,F. graminearumBeta-glucosidase was found to interact with ALPs. Our study is the first to report a class of wheat storage protein or gluten protein with biochemical functions. Due to its abundance in the grain and the important multi-functions, the results obtained in the current study are expected to have a significant impact on wheat research and industry.

Evidence is required to evaluate the effectiveness of population-level endoscopic screening for esophageal cancer (EC). In this study, 5,632 permanent residents aged 25-65 years from 6 villages in Hua County, Henan Province, China, were defined as the screening cohort and were offered intensive endoscopic screening. Residents of all 914 remaining villages in Hua County were included as the control cohort, and age-sex standardization was used to calculate the expected numbers of EC and upper gastrointestinal (GI) tract cancer cases and deaths in the screening cohort. The effectiveness of screening was assessed by comparing observed numbers of cases and deaths with expected numbers after 9-year follow-up of these screened subjects (2007-2016). In the screening cohort, 23 upper GI cancers (including 16 ECs) and 10 upper GI cancer deaths (including 5 EC deaths) were identified, and 47% (standardized incidence ratio = 0.53, 95% confidence interval (CI): 0.33, 0.87) and 66% (standardized mortality ratio = 0.34, 95% CI: 0.14, 0.81) reductions in cumulative EC incidence and mortality were found. For upper GI cancers, incidence and mortality were lowered by 43% (standardized incidence ratio = 0.57, 95% CI: 0.38, 0.86) and 53% (standardized mortality ratio = 0.47, 95% CI: 0.25, 0.88), respectively. This study showed that upper GI tract endoscopy is an effective population-level screening test for EC in high-risk regions.

Genome-wide association studies (GWAS) have been widely used to dissect the complex biosynthetic processes of plant metabolome. Most studies have used single-locus GWAS approaches, such as mixed linear model (MLM), and little is known about more efficient algorithms to implement multi-locus GWAS. Here, we report a comprehensive GWAS of 20 free amino acid (FAA) levels in kernels of bread wheat (Triticum aestivum L.) based on 14,646 SNPs by six multi-locus models (FASTmrEMMA, FASTmrMLM, ISISEM-BLASSO, mrMLM, pKWmEB, and pLARmEB). Our results showed that 328 significant quantitative trait nucleotides (QTNs) were identified in total (38, 8, 92, 45, 117, and 28, respectively, for the above six models). Among them, 66 were repeatedly detected by more than two models, and 155 QTNs appeared only in one model, indicating the reliability and complementarity of these models. We also found that the number of significant QTNs for different FAAs varied from 8 to 41, which revealed the complexity of the genetic regulation of metabolism, and further demonstrated the necessity of the multi-locus GWAS. Around these significant QTNs, 15 candidate genes were found to be involved in FAA biosynthesis, and one candidate gene (TraesCS1D01G052500, annotated as tryptophan decarboxylase) was functionally identified to influence the content of tryptamine in vitro. Our study demonstrated the power and efficiency of multi-locus GWAS models in crop metabolome research and provided new insights into understanding FAA biosynthesis in wheat.

International audience; Detection of senescence’s dynamics in crop breeding is time consuming and needs considerable details regarding its rate of progression and intensity. Normalized difference red-edge index (NDREI) along with four other spectral vegetative indices (SVIs) derived from unmanned aerial vehicle (UAV) based spatial imagery, were evaluated for rapid and accurate prediction of senescence. For this, 32 selected winter wheat genotypes were planted under full and limited irrigation treatments. Significant variations for all five SVIs: green normalize difference vegetation index (GNDVI), simple ratio (SR), green chlorophyll index (GCI), red-edge chlorophyll index (RECI), and normalized difference red-edge index (NDREI) among genotypes and between treatments, were observed from heading to late grain filling stages. The SVIs showed strong relationship (R2 = 0.69 to 0.78) with handheld measurements of chlorophyll and leaf area index (LAI), while negatively correlated (R2 = 0.75 to 0.77) with canopy temperature (CT) across the treatments. NDREI as a new SVI showed higher correlations with ground data under both treatments, similarly as exhibited by other four SVIs. There were medium to strong correlations (r = 0.23–0.63) among SVIs, thousand grain weight (TGW) and grain yield (GY) under both treatments. Senescence rate was calculated by decreasing values of SVIs from their peak values at heading stage, while variance for senescence rate among genotypes and between treatments could be explained by SVIs variations. Under limited irrigation, 10% to 15% higher senescence rate was detected as compared with full irrigation. Principle component analysis corroborated the negative association of high senescence rate with TGW and GY. Some genotypes, such as Beijing 0045, Nongda 5181, and Zhongmai 175, were selected with low senescence rate, stable TGW and GY in both full and limited irrigation treatments, nearly in accordance with the actual performance of these cultivars in field. Thus, SVIs derived from UAV appeared as a promising tool for rapid and precise estimation of senescence rate at maturation stages.

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 (ClinicalTrials.gov: NCT01688908) randomly selected from Hua County, Henan Province, China were interviewed. The EQ-5D-3L, 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-5D 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-5D index score of 0.948, and lower EQ-5D 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.

The association between human papillomavirus 31 (HPV31) DNA loads and the risk of cervical intraepithelial neoplasia grades 2 and 3 (CIN2–3) was evaluated among women enrolled in the atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesion (LSIL) triage study (ALTS), who were monitored semiannually over 2 years and who had HPV31 infections detected at ≥1 visit. HPV31 DNA loads in the first HPV31-positive samples and in a random set of the last positive samples from women with ≥2 HPV31-positive visits were measured by a real-time PCR assay. CIN2–3 was histologically confirmed at the same time as the first detection of HPV31 for 88 (16.6%) of 530 women. After adjustment for HPV31 lineages, coinfection with other oncogenic types, and the timing of the first positive detection, the odds ratio (OR) per 1-log-unit increase in viral loads for the risk of a concurrent diagnosis of CIN2–3 was 1.5 (95% confidence interval [CI], 1.2 to 1.9). Of 373 women without CIN2–3 at the first positive visit who had ≥1 later visit, 44 had subsequent diagnoses of CIN2–3. The initial viral loads were associated with CIN2–3 diagnosed within 6 months after the first positive visit (adjusted OR, 1.5 [95% CI, 1.0 to 2.4]) but were unrelated to CIN2–3 diagnosed later. For a random set of 49 women who were tested for viral loads at the first and last positive visits, changes in viral loads were upward and downward among women with and without follow-up CIN2–3 diagnoses, respectively, although the difference was not statistically significant. Results suggest that HPV31 DNA load levels at the first positive visit signal a short-term but not long-term risk of CIN2–3.

Arabinoxylans (AX) are major polymers of wheat grain cell walls and affect the end-use properties and nutritional quality. Total (TOT-AX), water-unextractable (WU-AX), and water-extractable (WE-AX) AX contents were determined in grain of 240 recombinant inbred wheat lines (RILs), derived from the cross PH82-2/Neixiang 188. A total of 195 SSR and STS markers were used to construct a genetic map and to detect quantitative trait loci (QTL). Wide ranges of variation in TOT-AX, WU-AX, and WE-AX contents were observed among the RILs, with line effects contributing the largest phenotypic variation. Broad sense heritabilities (h 2) were 0.50, 0.38 and 0.71, respectively. Inclusive composite interval mapping (ICIM) identified four additive QTL for TOT-AX content on chromosomes 1B, 1D, 3B and 5B, explaining 3.7–14.6 % of the phenotypic variance (PV), among which two were involved in significant additive × season interactions, contributing 0.5–2.4 % of the PV. Two additive QTL for WU-AX content were identified on chromosomes 1B and 1D, accounting for 6.4 and 8.6 % of the PV, respectively; both were involved in significant additive × season interactions, contributing 0.6–1.4 % of the PV. Nine additive QTL for WE-AX content were identified on chromosomes 1A, 1B, 2B, 3B, 5A, 5B, 6B, 7A and 7B, explaining 3.8–15.2 % of the PV, and three of them were involved in significant additive × season interactions, contributing 0.5–2.1 % of the PV. Two pairs of epistatic QTL, with significant epistatic × season interactions, were identified for TOT-AX and WU-AX contents, contributing 16.6 and 18.6 % of the PV, respectively. The QTL identified on chromosomes 1B (associated with rye secalin marker sec1), 5A, 5B and 7A showed stable effects on WE-AX content across seasons.

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.

Three novel QTL for peroxidase activity were mapped, and gene-specific markers for TaPod-A1 were developed and validated using RILs derived from the Doumai/Shi 4185 cross and 281 wheat cultivars. TaPod-A1 is within one of the three QTL. Peroxidase (POD) activity in grain is an important factor determining the color of flour and end-use products of wheat, such as noodles and steamed bread. Mapping QTL for POD activity, characterization of POD genes and development of gene-specific markers are important for molecular marker-assisted selection in wheat breeding. Quantitative trait loci (QTL) for POD activity in common wheat were mapped using a recombinant inbred line (RIL) population derived from a Doumai/Shi 4185 cross grown in four environments and genotyped using the wheat 90 K iSelect assay. Three novel QTL for POD activity, QPod.caas-3AL, QPod.caas-4BS and QPod.caas-5AS, were identified on chromosomes 3AL, 4BS and 5AS, explaining 5.3–21.2 % of phenotypic variance across environments. The full-length genomic DNA (gDNA) sequence of a POD gene, designated TaPod-A1, on chromosome 3A was characterized by homolog cloning and PCR verification. Two complementary dominant sequence-tagged site (STS) markers, POD-3A1 and POD-3A2, were developed based on single nucleotide polymorphisms (SNPs) between two alleles at the TaPod-A1 locus, amplifying 291- and 766-bp fragments in cultivars with lower and higher POD activities, respectively. The two gene-specific markers were mapped on chromosome 3AL using a set of Chinese Spring (CS) nulli-tetrasomic lines, and ditelosomic lines 3AL and 3AS. QTL analysis indicated that QPod.caas-3AL co-segregated with the gene-specific markers POD-3A1 and POD-3A2. POD-3A1 and POD-3A2 were verified on 281 wheat cultivars and advanced lines, and showed significant (P

Leaf rust, caused by Puccinia triticina, is an important foliar disease of wheat (Triticum aestivum L.) worldwide. In the present study, CIMMYT line 19HRWSN-122 and 36 lines with known Lr (leaf rust resistance) genes were inoculated with 13 Chinese P. triticina pathotypes for postulation of Lr genes at the seedling stage. Line 19HRWSN-122 showed high resistance to all 13 P. triticina pathotypes in the greenhouse, indicating that it carries effective seedling resistance. This may be due to a resistance gene combination, an effective gene to all pathotypes present in China or a new resistance gene. With the objective of mapping the putatively new gene for resistance to leaf rust, 20 F1, 280 F2 plants and 254 F2:3 lines from the cross 19HRWSN-122 × Zhengzhou 5389 (susceptible) were inoculated with P. triticina pathotype THJP in the greenhouse. Results based on the F1, F2 and F2:3 lines indicated that a single dominant gene, temporarily designated LrHR122, was present in 19HRWSN-122. Bulked segregant analysis was performed on equal amounts of genomic DNA from ten resistant and ten susceptible F2:3 lines. Molecular markers polymorphic between the resistant and susceptible bulks were used to genotype F2:3 lines. LrHR122 was linked to one SSR marker, one STS marker, one SCAR marker and three EST markers on chromosome 3DL. Marker SCS1302 609 co-segregated with LrHR122, and the closest flanking markers were BE442875 and STS24-16 at genetic distances of 0.4 and 0.4 cM, respectively. Lr24 is known to be located on chromosome 3DL near LrHR122. In seedling tests, lines with both LrHR122 and Lr24 showed high resistance to all 13 Chinese P. triticina pathotypes. According to the pedigree and chromosome position LrHR122 should be Lr24. Lr24 was closely linked to one SSR marker and three EST markers in the terminal region of 3DL. These markers should be useful for marker assisted selection in breeding leaf rust resistant wheat cultivars.

There is a growing interest in integrating biomaterial repositories into larger infrastructures in order to meet research demands. However, even for a single hospital or institute, where both population-based and multiple disease-based biobanks have existed for a long time, the integration of existing separate biobanks into a virtual cancer biobank is still challenging. The guidelines and procedures for biobanking are varied and not universally enforced or followed in separate biobanks. Within the last 2 years, we initiated a project to establish a centralized biobank facility in a common storage environment. Analyzing the challenges and interests of stakeholders for the biobanks, a working group comprised of representatives from the central and separate banks, ethic committees, and research administration offices reached an agreement to implement a central facility by following the ISBER best practices for biobanking, and including regular project reviews by the ethical and scientific boards. Furthermore, by implementing a modified minimum information system with biobank data sharing, a network based intra-hospital virtual cancer bank was established to facilitate sharing information of samples held by separate banks. Meanwhile, this virtual biobank network, which has integrated patient information from hospital health care systems, will gradually integrate follow-up information from the cancer registry office and data from epidemiology studies, providing controlled access for sample providers and resource users. In the future, this infrastructure designed for a single hospital may be helpful for building a broader virtual network for data and specimen exchanges.

The original article was corrected. Author Muhammad Kundi should instead read: Muhammad Sohail.

Background Wheat genetic resources have been used for genetic improvement since 1876, when Stephen Wilson (Transactions and Proceedings of the Botanical Society of Edinburgh 12: 286) consciously made the first wide hybrid involving wheat and rye in Scotland. Wide crossing continued with sporadic attempts in the first half of 19th century and became a sophisticated scientific discipline during the last few decades with considerable impact in farmers' fields. However, a large diversity of untapped genetic resources could contribute in meeting future wheat production challenges. Perspectives and conclusion Recently the complete reference genome of hexaploid (Chinese Spring) and tetraploid (Triticum turgidum ssp. dicoccoides) wheat became publicly available coupled with on-going international efforts on wheat pan-genome sequencing. We anticipate that an objective appraisal is required in the post-genomics era to prioritize genetic resources for use in the improvement of wheat production if the goal of doubling yield by 2050 is to be met. Advances in genomics have resulted in the development of high-throughput genotyping arrays, improved and efficient methods of gene discovery, genomics-assisted selection and gene editing using endonucleases. Likewise, ongoing advances in rapid generation turnover, improved phenotyping, envirotyping and analytical methods will significantly accelerate exploitation of exotic genes and increase the rate of genetic gain in breeding. We argue that the integration of these advances will significantly improve the precision and targeted identification of potentially useful variation in the wild relatives of wheat, providing new opportunities to contribute to yield and quality improvement, tolerance to abiotic stresses, resistance to emerging biotic stresses and resilience to weather extremes.

To accelerate genetic gains in breeding, physiological trait (PT) characterization of candidate parents can help make more strategic crosses, increasing the probability of accumulating favorable alleles compared to crossing relatively uncharacterized lines. In this study, crosses were designed to complement “source” with “sink” traits, where at least one parent was selected for favorable expression of biomass and/or radiation use efficiency—source—and the other for sink-related traits like harvest-index, kernel weight and grains per spike. Female parents were selected from among genetic resources—including landraces and products of wide-crossing (i.e. synthetic wheat)—that had been evaluated in Mexico at high yield potential or under heat stress, while elite lines were used as males. Progeny of crosses were advanced to the F4 generation within Mexico, and F4-derived F5 and F6 generations were yield tested to populate four international nurseries, targeted to high yield environments (2nd and 3rd WYCYT) for yield potential, and heat stressed environments (2nd and 4th SATYN) for climate resilience, respectively. Each nursery was grown as multi-location yield trials. Genetic gains were achieved in both temperate and hot environments, with most new PT-derived lines expressing superior yield and biomass compared to local checks at almost all international sites. Furthermore, the tendency across all four nurseries indicated either the superiority of the best new PT lines compared with the CIMMYT elite checks, or the superiority of all new PT lines as a group compared with all checks, and in some cases, both. Results support—in a realistic breeding context—the hypothesis that yield and radiation use efficiency can be increased by improving source:sink balance, and validate the feasibility of incorporating exotic germplasm into mainstream breeding efforts to accelerate genetic gains for yield potential and climate resilience.

Wheat improvement programs require rapid assessment of large numbers of individual plots across multiple environments. Vegetation indices (VIs) that are mainly associated with yield and yield-related physiological traits, and rapid evaluation of canopy normalized difference vegetation index (NDVI) can assist in-season selection. Multi-spectral imagery using unmanned aerial vehicles (UAV) can readily assess the VIs traits at various crop growth stages. Thirty-two wheat cultivars and breeding lines grown in limited irrigation and full irrigation treatments were investigated to monitor NDVI across the growth cycle using a Sequoia sensor mounted on a UAV. Significant correlations ranging from R2 = 0.38 to 0.90 were observed between NDVI detected from UAV and Greenseeker (GS) during stem elongation (SE) to late grain gilling (LGF) across the treatments. UAV-NDVI also had high heritabilities at SE (h2 = 0.91), flowering (F)(h2 = 0.95), EGF (h2 = 0.79) and mid grain filling (MGF) (h2 = 0.71) under the full irrigation treatment, and at booting (B) (h2 = 0.89), EGF (h2 = 0.75) in the limited irrigation treatment. UAV-NDVI explained significant variation in grain yield (GY) at EGF (R2 = 0.86), MGF (R2 = 0.83) and LGF (R2 = 0.89) stages, and results were consistent with GS-NDVI. Higher correlations between UAV-NDVI and GY were observed under full irrigation at three different grain-filling stages (R2 = 0.40, 0.49 and 0.45) than the limited irrigation treatment (R2 = 0.08, 0.12 and 0.14) and GY was calculated to be 24.4% lower under limited irrigation conditions. Pearson correlations between UAV-NDVI and GY were also low ranging from r = 0.29 to 0.37 during grain-filling under limited irrigation but higher than GS-NDVI data. A similar pattern was observed for normalized difference red-edge (NDRE) and normalized green red difference index (NGRDI) when correlated with GY. Fresh biomass estimated at late flowering stage had significant correlations of r = 0.30 to 0.51 with UAV-NDVI at EGF. Some genotypes Nongda 211, Nongda 5181, Zhongmai 175 and Zhongmai 12 were identified as high yielding genotypes using NDVI during grain-filling. In conclusion, a multispectral sensor mounted on a UAV is a reliable high-throughput platform for NDVI measurement to predict biomass and GY and grain-filling stage seems the best period for selection.

Four QTLs for adult-plant resistance to powdery mildew were mapped in the Zhou8425B/Chinese Spring population, and a new QTL on chromosome 3B was validated in 103 wheat cultivars derived from Zhou8425B. Zhou8425B is an elite wheat (Triticum aestivum L.) line widely used as a parent in Chinese wheat breeding programs. Identification of genes for adult-plant resistance (APR) to powdery mildew in Zhou8425B is of high importance for continued controlling the disease. In the current study, the high-density Illumina iSelect 90K single-nucleotide polymorphism (SNP) array was used to map quantitative trait loci (QTL) for APR to powdery mildew in 244 recombinant inbred lines derived from the cross Zhou8425B/Chinese Spring. Inclusive composite interval mapping identified QTL on chromosomes 1B, 3B, 4B, and 7D, designated as QPm.caas-1BL.1, QPm.caas-3BS, QPm.caas-4BL.2, and QPm.caas-7DS, respectively. Resistance alleles at the QPm.caas-1BL.1, QPm.caas-3BS, and QPm.caas-4BL.2 loci were contributed by Zhou8425B, whereas that at QPm.caas-7DS was from Chinese Spring. QPm.caas-3BS, likely to be a new APR gene for powdery mildew resistance, was detected in all four environments. One SNP marker closely linked to QPm.caas-3BS was transferred into a semi-thermal asymmetric reverse PCR (STARP) marker and tested on 103 commercial wheat cultivars derived from Zhou8425B. Cultivars with the resistance allele at the QPm.caas-3BS locus had averaged maximum disease severity reduced by 5.3%. This STARP marker can be used for marker-assisted selection in improvement of the level of powdery mildew resistance in wheat breeding.

ObjectivesEsophageal squamous cell carcinoma (ESCC) is the predominant form of esophageal carcinoma with extremely aggressive nature and low survival rate. The risk factors for ESCC in the high-incidence areas of China remain unclear. We used machine learning methods to investigate whether there was an association between the alterations of serum levels of certain chemical elements and ESCC.SettingsPrimary healthcare unit inAnyangcity, Henan Province of China.Participants100 patients with ESCC and 100 healthy controls matched for age, sex and region were included.Primary and secondary outcome measuresPrimary outcome was the classification accuracy. Secondary outcome was the p Value of the t-test or rank-sum test.MethodsBoth traditional statistical methods of t-test and rank-sum test and fashionable machine learning approaches were employed.ResultsRandom Forest achieves the best accuracy of 98.38% on the original feature vectors (without dimensionality reduction), and support vector machine outperforms other classifiers by yielding accuracy of 96.56% on embedding spaces (with dimensionality reduction). All six classifiers can achieve accuracies more than 90% based on the single most important element Sr. The other two elements with distinctive difference are S and P, providing accuracies around 80%. More than half of chemical elements were found to be significantly different between patients with ESCC and the controls.ConclusionsThese results suggest clear differences between patients with ESCC and controls, implying some potential promising applications in diagnosis, prognosis, pharmacy and nutrition of ESCC. However, the results should be interpreted with caution due to the retrospective design nature, limited sample size and the lack of several potential confounding factors (including obesity, nutritional status, and fruit and vegetable consumption and potential regional carcinogen contacts).

Background & Aims Chromoendoscopy with Lugol dye is used to screen for early-stage esophageal squamous dysplasia (ESD) and esophageal cancer. However, the sensitivity with which Lugol chromoendoscopy detects ESD or esophageal cancer has not been fully assessed in large populations in China. Methods From 2012 to 2016, a total of 15,264 residents in rural Hua County, Henan Province, which is a high-incidence area of esophageal cancer in China, were screened by Lugol chromoendoscopy. Biopsies were collected from endoscopically visualized lesions, identified before and after Lugol chromoendoscopy, and analyzed histologically. Biopsies were also collected from standard sites in the esophagus (28 and 33 cm distal to the incisors) if no abnormalities were found. We calculated the sensitivity with which Lugol chromoendoscopy detects esophageal dysplasia and carcinoma, using findings from biopsy analysis as the reference standard. Results A total 586 participants were found by biopsy analysis to have ESD or more severe lesions. After endoscopy images were reviewed twice, Lugol chromoendoscopy sensitivity values for the detection of mild, moderate, and severe dysplasia, and esophageal cancer, were 45.9%, 55.3%, 87.0%, and 97.7%, respectively. ESDs were most frequently missed by Lugol chromoendoscopy in younger patients and men with moderate levels of dysplasia. Conclusion In a screening analysis of a general population in China, we found Lugol chromoendoscopy to identify individuals with ESD with lower levels of sensitivity (46%–87%) than previously believed, although it identified patients with esophageal cancer with almost 98% sensitivity. Prospective studies are needed to evaluate the clinical significance of esophageal lesions that are not detected by endoscopy.

Objectives Hysterectomy is one of the most common surgical procedures performed on women in developed countries; however, little is known about the epidemiology of hysterectomy in low-income to middle-income regions. This study seeks to evaluate the prevalence of hysterectomy and its risk factors in rural China. Methods Questionnaires were collected from 3328 female adults aged 25–69 years in rural Anyang, China, in 2009–2011. Hysterectomy status was ascertained by the gynaecologist at the time of cytological test. Univariate and multivariate regression analyses were performed to assess the risk factors for hysterectomy. Results The overall prevalence of hysterectomy was 3.31% (110/3328). Women above the age of 40 years had a higher prevalence of prior hysterectomy, compared with those aged 25–39 years (5.01% vs 0.33%). Obesity was marginally related with a higher risk of hysterectomy (adjusted OR=1.59; 95% CI 0.99 to 2.56; body mass index (BMI) ≥28.0 vs 18.5 ≤ BMI

Trehalose 6-phosphate phosphatase (TPP) dephosphorylates trehalose 6-phosphate to trehalose, an important growth regulator, and is involved in starch accumulation and grain yield. In this study, wheat TPP homologs were isolated from chromosomes 6AL, 6BL, and 6DL, designated as TaTPP-6AL1, TaTPP-6BL1, and TaTPP-6DL1, respectively. Sequence alignment showed a single-nucleotide polymorphism (SNP) at TaTPP-6AL1 locus between cultivars with contrasting thousand grain weight (TGW), forming alleles TaTPP-6AL1a and TaTPP-6AL1b, respectively. A cleaved amplified polymorphic sequence (CAPS) marker, TaTPP-6AL1-CAPS, was developed to differentiate the two alleles. TaTPP-6AL1 was mapped within the interval of IWB65749 and IWB60449 in a recombinant inbred line (RIL) population derived from Zhou8425B/Chinese Spring using the wheat 90K SNP assay. A QTL for TGW identified in the interval explained 12.1–19.1% of the phenotypic variance across five environments. Association analysis on 141 Chinese wheat cultivars also indicated a significant correlation of TaTPP-6AL1 with TGW. In conclusion, TaTPP-6AL1 and its functional marker are valuable to improve grain yield in wheat breeding.

Leaf rust is a destructive foliar disease of common wheat (Triticum aestivum L.) worldwide. Growing resistant cultivars with adult plant resistance (APR) is an effective means to control the disease. In the present study, 244 recombinant inbred lines (RILs) from the Zhou 8425B/Chinese Spring cross were phenotyped for leaf rust severities during the 2011-2012, 2012-2013, 2013-2014 and 2014-2015 cropping seasons at Baoding, Hebei province, and 2012-2013 and 2013-2014 cropping seasons in Zhoukou, Henan province. The population was genotyped using the high-density Illumina iSelect 90K SNP assay and SSR markers. Inclusive composite interval mapping identified eight QTL, designated as QLr.hebau-2AL, QLr.hebau-2BS, QLr.hebau-3A, QLr.hebau-3BS, QLr.hebau-4AL, QLr.hebau-4B, QLr.hebau-5BL and QLr.hebau-7DS, respectively. QLr.hebau-2BS, QLr.hebau-3A, QLr.hebau-3BS and QLr.hebau-5BL were derived from Zhou 8425B, whereas the other four were from Chinese Spring. Three stable QTL on chromosomes 2BS, 4B and 7DS explained 7.5-10.6%, 5.5-24.4% and 11.2-20.9% of the phenotypic variance, respectively. QLr.hebau-2BS in Zhou 8425B might be the same as LrZH22 in Zhoumai 22; QLr.hebau-4B might be the residual resistance of Lr12, and QLr.hebau-7DS is Lr34. QLr.hebau-2AL, QLr.hebau-3BS, QLr.hebau-4AL and QLr.hebau-5BL are likely to be new APR QTL. These QTL and closely linked SNP markers can be used for fine mapping, candidate gene discovery, and marker-assisted selection in wheat breeding.

Leaf senescence is an important trait for yield improvement under stress. In the present study, 207 F2:4 random inbred lines (RILs) derived from the Jingdong 8/Aikang 58 cross were investigated under limited and full irrigation environments at two locations during the 2011–2012 and 2012–2013 cropping seasons. The RILs were genotyped with 149 SSR markers and QTLs for leaf senescence-related traits and heading dates (HD) were analyzed by inclusive composite interval mapping. The broad sense heritabilities of normalized difference vegetation index at Zadoks47 (NDVIv) and at Zadoks75 (NDVIg), leaf senescence rate (LSR), leaf senescence scored visually (LSS), leaf area index (LAI) and HD were 0.37–0.54, 0.39–0.48, 0.4–0.45, 0.56–0.58, 0.64–0.79 and 0.82–0.86, respectively. There were significant correlations between NDVIg and LSR (r = −0.55 to −0.70), NDVIg and LSS (r = −0.61 to −0.61), and LSS and LSR (r = 0.48–0.68). NDVIv and LAIv explained 18.5 % and 19.4 % of the variation in grain yield under limited irrigation, respectively. Forty five QTLs were distributed on 15 chromosomes. The respective numbers of QTLs for NDVIv, NDVIg, LSR, LSS and HD were 10, 10, 9, 9 and 7 across all eight environments. Previously unreported QTLs were found on chromosomes 1A, 2D, 5B, 7A and 7D for NDVI, on 6D for LSR and 5B for LSS. QNDVIv.caas-4A explained 23.7–56.6 % of the phenotypic variation (PV) for NDVIv and was stably expressed in four environments. In contrast, QNDVIg.caas-4B.2 explained 13.2–16.0 % of PV but was only expressed in full irrigation. Pleiotropic QTLs were detected; QNDVIv.caas-5B, explaining 22.9–35.9 % of PV, had an effect on LSS, and QNDVIg.caas-4D, accounting for 11.5–28.5 % of PV, also influenced NDVIv. QTLs controlling LSR, QLSR.caas-4D and QLSR.caas-3B, also increased thousand kernel weight and grain yield, indicating that rapid senescence increased grain filling rate. Some QTLs such as QNDVIg.caas-1A.1, QLSR.caas-2A, QLSS.caas-2B, QLSS.caas-3B, QLSS.caas-5B and QLSS.caas-2D.1 were detected only under limited irrigation. These drought stress-induced QTLs could be valuable for improving drought resistance in wheat.

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 (

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.

Background: Despite the established link between oral human papillomavirus (HPV) infection and a subset of oropharyngeal squamous cell carcinoma (OSCC), little is known about the epidemiology of oral HPV infection among healthy adults in China. Methods: Oral swab specimens and questionnaires were collected from 5,410 individuals (ages 25–65 years). HPV DNA in oral exfoliated cells was tested by general primer-mediated (SPF1/GP6+) PCR and sequencing. Univariate and multivariate analyses were performed to assess the associations between exposure factors and oral infection. Results: Alpha mucosal HPV types were detected in 0.67% [95% confidence interval (CI), 0.47%–0.93%] of 5,351 β-globin–positive specimens, and cutaneous HPV in 5.46% (95% CI, 4.86%–6.10%). HPV 16 and 3 were the most prevalent types of α mucosal (0.43%; 95% CI, 0.27%–0.64%) and cutaneous HPV (4.17%; 95% CI, 3.65%–4.74%), respectively. The prevalence of α mucosal HPV decreased with increasing age (25–65 years) from 0.93% to 0.36% (Ptrend = 0.033), and was associated with self-reported history of oral disease [adjusted odds ratio (OR), 4.78; 95% CI, 1.07–21.41]. In 1,614 heterosexual couples, cutaneous HPV in one partner was found to increase the other partner's risk of cutaneous HPV infection (adjusted OR, 2.33; 95% CI, 1.22–4.48). Conclusions: Oral HPV infection, particularly with α mucosal types, is rare among healthy adults in China. A younger age and a history of oral disease imply higher risk of α mucosal HPV infection. Impact: This study addresses the paucity of epidemiological data on oral HPV infection among healthy population in China. Cancer Epidemiol Biomarkers Prev; 23(10); 2101–10. ©2014 AACR.

Leaf rust and powdery mildew, caused by Puccinia triticina and Blumeria graminis f. sp. tritici, respectively, are widespread fungal diseases of wheat (Triticum aestivum L.). Development of cultivars with durable resistance is crucially important for global wheat production. This paper reviews the progress of genetic study and application of adult plant resistance (APR) to wheat leaf rust and powdery mildew. Eighty leaf rust and 119 powdery mildew APR quantitative trait loci (QTL) have been reported on 16 and 21 chromosomes, respectively, in over 50 publications during the last 15 yr. More important, we found 11 loci located on chromosomes 1BS, 1BL, 2AL, 2BS (2), 2DL, 4DL, 5BL, 6AL, 7BL, and 7DS showing pleiotropic effects on resistance to leaf rust, stripe rust, and powdery mildew. Among these, QTL on chromosomes 1BL, 4DL, and 7DS also correlate with leaf tip necrosis. Fine mapping and cloning of these QTL will be achieved with the advent of cheaper high-throughput genotyping technologies. Germplasm carrying these potential resistance genes will be useful for developing cultivars with durable multidisease resistance. In addition to its non-NBS–LRR (nucleotide binding site–leucine rich repeat) structure, the senescence-like processes induced by Lr34 could be the reason for durability of resistance; however, more information is needed for a full understanding of the molecular mechanism related to durability. Adult plant resistance genes have been used by CIMMYT for more than 30 yr and have also been transferred to many Chinese wheat varieties through shuttle breeding.

We conducted a joint (pooled) analysis of three genome-wide association studies (GWAS) of esophageal squamous cell carcinoma (ESCC) in individuals of Chinese ancestry (5,337 ESCC cases and 5,787 controls) with 9,654 ESCC cases and 10,058 controls for follow-up. In a logistic regression model adjusted for age, sex, study and two eigenvectors, two new loci achieved genome-wide significance, marked by rs7447927 at 5q31.2 (per-allele odds ratio (OR) = 0.85, 95% confidence interval (CI) = 0.82-0.88; P = 7.72 × 10(-20)) and rs1642764 at 17p13.1 (per-allele OR = 0.88, 95% CI = 0.85-0.91; P = 3.10 × 10(-13)). rs7447927 is a synonymous SNP in TMEM173, and rs1642764 is an intronic SNP in ATP1B2, near TP53. Furthermore, a locus in the HLA class II region at 6p21.32 (rs35597309) achieved genome-wide significance in the two populations at highest risk for ESSC (OR = 1.33, 95% CI = 1.22-1.46; P = 1.99 × 10(-10)). Our joint analysis identifies new ESCC susceptibility loci overall as well as a new locus unique to the population in the Taihang Mountain region at high risk of ESCC.

Wheat seed storage proteins, especially glutenins and gliadins, have unique functional properties giving rise to a wide array of food products for human consumption. The wheat seed storage proteins, however, are also the most common cause of food-related allergies and intolerances, and it has become crucially important to understand their composition, variation and functional properties and interface this knowledge with the grain handling industry as well as the breeders. This review focuses on advances in understanding the genetics and function of storage proteins and their application in wheat breeding programs. These include: (1) The development and validation of high-throughput molecular marker systems for defining the composition and variation of low molecular weight glutenin subunits (LMW-GS) genes and a summary of the more than 30 gene-specific markers for rapid screening in wheat breeding programs; (2) The identification of more than 100 alleles of storage proteins in wild species provide candidate genes for future quality improvement; (3) The documentation of quality effects of individual LMW-GS and HMW-GS for improving end-use quality; and (4) The analysis of α-gliadin genes on chromosomes 6A and 6D with non-toxic epitopes as potential targets to develop less toxic cultivars for people with celiac disease. Genomic and proteomic technologies that will continue to provide new tools for understanding variation and function of seed storage proteins in wheat are discussed.

Stripe rust is a major fungal disease of wheat. It frequently becomes epidemic in southeastern Gansu province, a stripe rust hot spot in China. Evaluations of wheat germplasm response are crucial for developing cultivars to control the disease. In total, 57 wheat cultivars and lines from Europe and other countries, comprising 36 cultivars with documented stripe rust resistance genes and 21 with unknown genes, were tested annually with multiple races of Puccinia striiformis f. sp. tritici in the field at Tianshui in Gansu province from 1993 to 2013. Seven wheat lines were highly resistant, with infection type (IT) 0 during the entire period; 16 were moderately resistant (IT 0;-2); and 26 were moderately susceptible (IT 0;-4), with low maximum disease severity compared with the susceptible control Huixianhong. ‘Strampelli’ and ‘Libellula’, with three and five quantitative trait loci, respectively, for stripe rust resistance have displayed durable resistance in this region for four decades. Ten cultivars, including ‘Lantian 15’, ‘Lantian 26’, and ‘Lantian 31’, with stripe rust resistance derived from European lines, were developed in our breeding program and have made a significant impact on controlling stripe rust in southeastern Gansu. Breeding resistant cultivars with multiple adult-plant resistance genes seems to be a promising strategy in wheat breeding for managing stripe rust in this region and other hot spots.

The OsGS3 gene plays a principal role in controlling grain weight and grain length in rice. However, the function of an orthologous gene TaGS in wheat has not been analyzed to date. In the present study, we cloned the gDNA of TaGS gene, designated TaGS-D1, with four exons and three introns on chromosome 7DS by a comparative genomics approach. The cDNA of TaGS-D1 is 255 bp, and it encodes 85 amino acids. We also found a plant-specific organ size regulation domain in the deduced polypeptide, indicating that TaGS-D1, like OsGS3, does not belong to the PEBP family. DNA sequencing of the TaGS-D1 locus revealed no diversity in the coding sequence of exons, but there was a single nucleotide polymorphism (SNP) in the first intron, and 30 SNPs, a 40-bp InDel and a 3-bp InDel were found in the second intron between genotypes with higher and lower thousand grain weights (TGW). Based on the 40-bp InDel, a co-dominant STS marker, designated GS7D, was developed to discriminate the two alleles. GS7D was 8.0 cM from Xbarc184 located on chromosome 7DS by linkage mapping. A QTL for TGW and grain length at GS7D locus explained up to 16.3 and 7.7 %, respectively, of the phenotypic variances in a RIL population derived from Doumai/Shi 4185 grown in Shijiazhuang and Beijing. One hundred and seventy-five Chinese wheat cultivars were genotyped with GS7D, indicating that TaGS-D1 was significantly associated with grain weight. The allelic distribution at the TaGS-D1 locus showed that the frequencies of TaGS-D1a were high in cultivars from Serbia, Japan, Australia, Canada, and the Northeastern Spring Wheat and Northern Winter Wheat Regions of China.

Meeting demands for increased cereal production in China is a great challenge and this paper provides updated information on cereal production and the potential adaptation of cropping systems to climate change, as well as on progress in improving yield potential and developing molecular markers and GM cereals in China. Maize production and soybean imports are increasing significantly to meet the strong demand for feed by a rapidly growing livestock industry. Extension of the rice and maize growing seasons in northeastern China and improvement of the cropping system through delayed wheat planting have contributed to improving cereal productivity despite changing climatic conditions. Significant improvements in yield potential of rice, maize, and wheat have been achieved. Comparative genomics has been successfully used to develop and validate functional markers for processing quality traits in wheat, and also for developing new varieties. Although transgenic Bt rice and maize, and maize expressing phytase have been developed, their commercialization has not been officially permitted. International collaboration has contributed significantly to cereal production by providing germplasm and improved crop management practices. Full integration of applied molecular technologies into conventional breeding programs and promotion of lower-input technologies, will play a key role in increasing and sustaining future cereal production.

The development and utilization of outstanding germplasm in breeding programs can expedite breeding process. The high yielding variety Mianmai 37, grown widely in southwestern China, has been used widely in breeding programs. Comparisons between Mianmai 37 and its derivatives for yield and yield components were conducted. Simple sequence repeat (SSR) markers were used to test the frequency of specific alleles transferred from Mianmai 37 to its derivative culti-var Mianmai 367. The results indicated that the yield of the derivative cultivars was significantly higher than Mianmai 37, due to an increased grain number per spike. Favorable traits from Mianmai 37 such as resistance to stripe rust, were trans-ferred to its derivatives. At molecular level, 78.9% loci in Mianmai 367 were derived from Mianmai 37 with 75.0, 83.6 and 74.2% from A, B and D genomes, respectively. Mianmai 367 shared common loci with its parent Mianmai 37, such as re-gions Xgwm374-Xbarc167-Xbarc128-Xgwm129-Xgwm388-Xbarc101 on chromosome 2B and Xwmc446-Xwmc366- Xwmc533-Xbarc164-Xwmc418 on chromosome 3B, these regions were associated with grain number, 1000-kernel weight and resistance. The preferred transmission of alleles from Mianmai 37 to its derivatives probably can be explained by the strong selection pressures because of its favorable agronomic traits and the disease resistance.

Seedling vigor is an important trait characterized by rapid development of vegetative cover above the soil surface, particularly in rainfed environments. To elucidate the genetic basis of seedling vigor, 207 F2:4 lines derived from Jingdong 8/Aikang 58 were investigated in the field at Beijing and Gaoyi, Hebei province, during the 2011–2012 and 2012–2013 cropping seasons. A total of 148 SSR markers polymorphic between the parents, and the RhtD1b-specific marker were used to map QTL for seedling vigor by inclusive composite interval mapping (ICIM). Normalized difference vegetation index (NDVI) and ground cover (GC) before winter and in late spring showed a continuous distribution. Significant differences in NDVI and GC among lines were detected. Broad-sense heritability of NDVI and GC ranged from 0.69 to 0.74 based on the mean values averaged across four environments. GC was highly correlated with NDVI (r = 0.74–0.85, P

Pronounced anther extrusion (AE) is associated with field resistance to Fusarium head blight (FHB), one of the most devastating diseases of wheat globally. In this study, two recombinant inbred line (RIL) populations were used to map quantitative trait loci (QTL) for AE and field FHB resistance and to investigate the association of both traits at the genetic level. Furthermore, two panels of International Maize and Wheat Improvement Center (CIMMYT) wheat breeding lines were evaluated to describe the phenotypic association between the two traits in detail. Highly significant negative correlation was identified between AE and FHB severity in the two populations and the two panels, with r-values ranging from 0.55 to 0.74. QTL analysis in the two RIL populations identified 12 QTL for AE and nine for FHB resistance, of which five QTL located on chromosomes 3BL, 4BS, 4DS, 5AL, and 5BL were associated with both AE and FHB, collectively explaining over 50% of phenotypic variation for FHB. The QTL on chromosomes 4BS, 4DS, 5AL, and 5BL were closely linked to Rht-B1, Rht-D1, Vrn-A1, and Vrn-B1 genes, respectively. In conclusion, AE is closely related to field FHB resistance and could be used as a morphological marker in wheat breeding for field FHB resistance.

Leaf rust, caused by Puccinia triticina, is one of the major wheat diseases worldwide and poses a constant threat to common wheat (Triticum aestivum L.) production and food security. Results from the F2 and F2:3 populations derived from a cross between resistant line Fundulea 900 and susceptible cultivar Thatcher indicated that a single dominant gene, tentatively designated LrFun, conferred resistance to leaf rust. In order to identify other possible genes in Fundulea 900, nine P. triticina pathotypes avirulent on Fundulea 900 were used to inoculate F2:3 families. The results showed that at least two leaf rust resistance genes were present in Fundulea 900. A total of 1,706 pairs of simple sequence repeat (SSR) primers were used to test the parents and resistant and susceptible bulks. Eight polymorphic markers from chromosome 7BL were used for genotyping the F2 and F2:3 populations. LrFun was linked to eight SSR loci on chromosome 7BL. The two closest flanking SSR loci were Xgwm344 and Xwmc70, with genetic distances of 4.4 and 5.7 cM, respectively. At present four leaf rust resistance genes, Lr14a, Lr14b, Lr68 and LrBi16, are located on chromosome 7BL. In a seedling test with 12 P. triticina isolates, the reaction patterns of LrFun were different from those of lines carrying Lr14a, Lr14b and LrBi16. Lr68 is an adult plant resistance gene, and it is different from the seedling resistance gene LrFun. Therefore, we concluded that LrFun is a new leaf rust resistance gene.

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, explaining 5.6%, 5.2% and 3.8% of the phenotypic variation, respectively. These results provide useful information for improving starch quality in common wheat.