The plateau environment not only affects the development of concrete's early strength but also damages its durability during its service life.This paper summarized and analyzed the impact of plateau environments o...The plateau environment not only affects the development of concrete's early strength but also damages its durability during its service life.This paper summarized and analyzed the impact of plateau environments on concrete’properties and proposed methods to improve the performance of concrete in plateau environment.The results indicated that low humidity and high evaporation rates in plateau regions inhibit the hydration of cement in concrete,leading to an increased content of micro-pores ranging from 500 to 1000 nm and raising the risk of early-stage cracking,thus reducing the impermeability of concrete.The low atmospheric pressure(AP)condition of 60 kPa decreases the entrained air content in concrete by over 20%,diminishes the pores under 200μm,and increases the average air-voids diameter and spacing factor,resulting in a decrease of more than 5%in the 28 d compressive strength of concrete.Consequently,the durability of concrete is compromised.Saponin and rosinbased air-entraining agents are recommended to improve the performance of concrete in plateau environments.Nanoparticles also aid in stabilizing bubbles in such conditions.Selecting low-heat specialty cements,increasing the amount of cement used,and extending the curing period are also vital measures to enhance the performance of plateau concrete.展开更多
The objective of this review is to describe events in China and elsewhere that are related to the discovery, genetic identification, use, and ultimate break-down of a single wheat gene for resistance to stripe rust, n...The objective of this review is to describe events in China and elsewhere that are related to the discovery, genetic identification, use, and ultimate break-down of a single wheat gene for resistance to stripe rust, namely Yr24/Yr26. In our retrospective analysis there was an early assumption of at least three genes at or near the locus, which caused an erroneous presumption of genetic diversity for resistance. It is an example of another boom and bust cycle in plant breeding with races virulent to Yr26(V26 races) now being the majority race group in the Chinese Pst population. We have attempted to present our story in a historical and personal context demonstrating research inputs from different national and international groups, as well as some significant contemporary side issues. It covers the period from the late 1980 s to 2017, during which significant rapid advances in the molecular biology of host: pathogen genetics occurred. We attempt to describe both successes and drawbacks in our work.展开更多
Most modern wheat cultivars were selected on the basis of yield-related indices measured under optimal fertilizer and irrigation inputs.With climate change,land degradation and salinity caused by sea water encroachmen...Most modern wheat cultivars were selected on the basis of yield-related indices measured under optimal fertilizer and irrigation inputs.With climate change,land degradation and salinity caused by sea water encroachment,wheat is increasingly subjected to environmental stress.Moreover,expanding urbanization increasingly encroaches upon prime agricultural land in countries like China,and alternative cropping areas must be found.Some of these areas have moderate constraining factors,such as salinity.Therefore,it is important to investigate whether current genetic materials and breeding procedures are maintaining adequate variability to address future problems caused by abiotic stress.In this study,a panel of 307 wheat accessions,including local landraces,exotic cultivars used in Chinese breeding programs and Chinese cultivars released during different periods since1940,were subjected to a genome-wide association study to dissect the genetic basis of salinity tolerance.Both marker-based and pedigree-based kinship analyses revealed that favorable haplotypes were introduced in some exotic cultivars as well as a limited number of Chinese landraces from the 1940 s.However,improvements in salinity tolerance during modern breeding are not as obvious as that of yield.To broaden genetic diversity for increasing salt tolerance,there is a need to refocus attention on local landraces that have high degrees of salinity tolerance and carry rare favorable alleles that have not been exploited in breeding.展开更多
Wheat crops in China are constantly challenged by stripe rust. Deployment of cultivars with diverse resistances is the best strategy to control the disease. A recombinant inbred line(RIL) population derived from a cro...Wheat crops in China are constantly challenged by stripe rust. Deployment of cultivars with diverse resistances is the best strategy to control the disease. A recombinant inbred line(RIL) population derived from a cross between the resistant cultivar Chakwal 86 and susceptible landrace Mingxian 169 was studied in multiple environments to examine the underlying genetics and to identify quantitative trait loci(QTL) for stripe rust resistance.One hundred and twenty-eight RILs were genotyped with wheat 35 K SNP array and a genome-wide linkage map with 1480 polymorphic SNP markers, or bins, was constructed.Two major QTL on chromosomes 1BL and 3BS, and one minor QTL on 6BS had significant effects in reducing stripe rust severity. The QTL were validated using composite interval mapping(CIM) and inclusive composite interval mapping(ICIM). These methods explained59.0%–74.1% of the phenotype variation in disease response. The QTL on chromosome 1 BL was confirmed to be Yr29/Lr46 and the one on 3BS was the resistance allele identified in CIMMYT germplasm but was not Yr30/Sr2. The QTL on 6BS probably corresponded to previously known QTL. RILs with combined QTL were more resistant than those with single or no QTL. Kompetitive allele-specific PCR(KASP) assays for the QTL with largest effect QTL on chromosome 3BS were performed on a subset of RILs and 150 unrelated wheat lines. The QTL on 3BS with its linked KASP markers can be used in marker-assisted selection to improve stripe rust resistance in breeding programs.展开更多
The development and deployment of diverse resistance sources in new wheat cultivars underpin the durable control of stripe rust.In the present study,two loci for adult plant resistance(APR),QYr SM155.1 and QYr SM155.2...The development and deployment of diverse resistance sources in new wheat cultivars underpin the durable control of stripe rust.In the present study,two loci for adult plant resistance(APR),QYr SM155.1 and QYr SM155.2,were identified in the Chinese wheat breeding line Shaanmai 155.QYr SM155.1 was mapped to a 3.0-c M interval between the single-nucleotide polymorphism(SNP)markers AX-109583610 and AX-110907562 on chromosome arm 2 BL.QYr SM155.2 was mapped to a 2.1-c M interval flanked by the SNP markers AX-110378556 and AX-86173526 on chromosome arm 7 AS.A genome-wide association study was used to identify markers associated with APR in a panel of 411 spring wheat lines.Thirteen and 11 SNPs were significantly associated with QYr SM155.1 and QYr SM155.2,respectively,corresponding to physical intervals of 653.75–655.52 Mb on 2 BL and 81.63–83.93 Mb on7 AS.To characterize the haplotype variation and the distribution of these QTL,haplotype analysis was performed based on these SNPs in an independent panel of 1101 worldwide wheat accessions.Three major haplotypes(2 B_h1,2 B_h2,and 2 B_h3)for QYr SM155.1 and four major haplotypes(7 A_h1,7 A_h2,7 A_h3,and 7 A_h4)for QYr SM155.2 were identified.Accessions individually harboring QYr SM155.1_h1 and QYr SM155.2_h1 haplotypes and their combination displayed resistance.Additional assays of 1306 current Chinese cultivars and breeding lines using markers flanking QYr SM155.1 and QYr SM155.2 indicated that the resistance haplotypes of the two QTL were present in respectively 1.45%and 14.16%of lines.Increasing resistance haplotype frequencies at these two loci using marker-assisted selection should benefit wheat production in China.展开更多
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...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.展开更多
Stay-green(SG)in wheat is a beneficial trait that increases yield and stress tolerance.However,conventional phenotyping techniques limited the understanding of its genetic basis.Spectral indices(SIs)as non-destructive...Stay-green(SG)in wheat is a beneficial trait that increases yield and stress tolerance.However,conventional phenotyping techniques limited the understanding of its genetic basis.Spectral indices(SIs)as non-destructive tools to evaluate crop temporal senescence provide an alternative strategy.Here,we applied Sls to monitor the senescence dynamics of 565 diverse wheat accessions from anthesis to maturation stages over 2 field seasons.Four Sis(normalized difference vegetation index,green normalized difference vegetation index,normalized difference red edge index,and optimized soil-adjusted vegetation index)were normalized to develop relative stay-green scores(RSGS)as the SG indicators.An RSGS-based genome-wide association study identified 47 high-confidence quantitative trait loci(QTL)harboring 3,079 single-nucleotide polymorphisms associated with SG and 1,085 corresponding candidate genes.Among them,15 QTL overlapped or were adjacent to known SG-related QTL/genes,while the remaining QTL were novel.Notably,a set of favorable haplotypes of SG-related candidate genes such as TraesCS2A03G1081100,TracesCS6B03G0356400,and TracesCS2B03G1299500 are increasing following the Green Revolution,further validating the feasibility of the pipeline.This study provided a valuable reference for further quantitative SG and genetic research in diverse wheat panels.展开更多
Dear Editor,Wheat is one of the most important food crops.In recent years,factors such as global warming have led to the frequent occurrence of extreme weather,altering the epidemic patterns of crop diseases and pests...Dear Editor,Wheat is one of the most important food crops.In recent years,factors such as global warming have led to the frequent occurrence of extreme weather,altering the epidemic patterns of crop diseases and pests and posing severe challenges to food security(Savary et al.2019).Wheat yellow rust(YR),also known as stripe rust,is caused by the biotrophic fungus Puccinia striiformis Westend f.sp.tritici(Pst)and remains one of the most devastating diseases threatening global wheat production(Chen 2020;Hovmoller et al.2023).展开更多
Single-nucleotide polymorphisms(SNPs)arewidely used asmolecularmarkers for constructing genetic linkage maps in wheat.Compared with available SNP-based genotyping platforms,a genotyping by target sequencing(GBTS)syste...Single-nucleotide polymorphisms(SNPs)arewidely used asmolecularmarkers for constructing genetic linkage maps in wheat.Compared with available SNP-based genotyping platforms,a genotyping by target sequencing(GBTS)system with capture-in-solution(liquid chip)technology has become the favored genotyping technology because it is less demanding and more cost effective,flexible,and user-friendly.In this study,a new GenoBaits WheatSNP16K(GBW16K)GBTS array was designed using datasets generated by the wheat 660K SNP array and resequencing platforms in our previous studies.The GBW16K array contains 14868 target SNP regions that are evenly distributed across the wheat genome,and 37669 SNPs in these regions can be identified in a diversity panel consisting of 239wheat accessions from around theworld.Principal component and neighbor-joining analyses using the called SNPs are consistent with the pedigree information and geographic distributions or ecological environments of the accessions.For the GBW16K marker panel,the average genetic diversity among the 239 accessions is 0.270,which is sufficient for linkage map construction and preliminary mapping of targeted genes or quantitative trait loci(QTLs).A genetic linkage map,constructed using the GBW16K array-based genotyping of a recombinant inbred line population derived from a cross of the CIMMYT wheat line Yaco“S”and the Chinese landrace Mingxian169,enables the identification of Yr27,Yr30,and QYr.nwafu-2BL.4 for adult-plant resistance to stripe rust from Yaco“S”and of Yr18 from Mingxian169.QYr.nwafu-2BL.4 is different from any previously reported gene/QTL.Three haplotypes and six candidate genes have been identified for QYr.nwafu-2BL.4 on the basis of haplotype analysis,micro-collinearity,gene annotation,RNA sequencing,and SNP data.This array provides a new tool for wheat genetic analysis and breeding studies and for achieving durable control of wheat stripe rust.展开更多
Repeated occurrences of extreme weather events,such as low temperatures,due to global warming present a serious risk to the safety of wheat production.Quantitative assessment of frost damage can facilitate the analysi...Repeated occurrences of extreme weather events,such as low temperatures,due to global warming present a serious risk to the safety of wheat production.Quantitative assessment of frost damage can facilitate the analysis of key genetic factors related to wheat tolerance to abiotic stress.We collected 491 wheat accessions and selected four image-based descriptors(BLUE band,RED band,NDVI,and GNDVI)to quantitatively assess their frost damage.Image descriptors can complement the visual estimation of frost damage.Combined with genome-wide association study(GWAS),a total of 107 quantitative trait loci(QTL)(r^(2) ranging from 0.75%to 9.48%)were identified,including the wellknown frost-resistant locus Frost Resistance(FR)-A1/Vernalization(VRN)-A1.Additionally,through quantitative gene expression data and mutation experience verification experiments,we identified two other frost tolerance candidate genes TraesCS2A03G1077800 and TraesCS5B03G1008500.Furthermore,when combined with genomic selection(GS),image-based descriptors can predict frost damage with high accuracy(r≤0.84).In conclusion,our research confirms the accuracy of image-based high-throughput acquisition of frost damage,thereby supplementing the exploration of the genetic structure of frost tolerance in wheat within complex field environments.展开更多
The fungus Puccinia striiformis f.sp.tritici(Pst)is the causal agent of wheat stripe rust which constitutes a major limitation to wheat production.Cloning and applying disease-resistant genes are considered as an effe...The fungus Puccinia striiformis f.sp.tritici(Pst)is the causal agent of wheat stripe rust which constitutes a major limitation to wheat production.Cloning and applying disease-resistant genes are considered as an effective solution.Chinese wheat cultivar Xingzi 9104(XZ9104)has exhibited durable resistance across multiple environments since its release.Through quantitative trait loci(QTL)analysis,eight QTL were found on chromosome arms 1BS,1BL,2AL,2BL,3BS,4BL,5BL and 7BL.YrXZ identified as 1RS.1BL translocation conferred race-specific all-stage resistance to Pst race CYR23.QYrxz.nwafu-1BL.6 and QYrxz.nwafu-3BS.7 were considered as the adult plant resistance genes Yr29 and Yr30,respectively.Notably,QYrxz.nwafu-2BL.5 accounted for 15.75-47.63%of the phenotypic variation across diverse environments and its pyramiding with Yr29 and Yr30 can confer high level of resistance.Other QTL were environment-dependent with minor effects.To clone the above resistance genes,we created a population of over 2,000 M5 mutants in XZ9104 using ethylmethane sulfonate(EMS)mutagenesis and screened various types of susceptible mutants.Using the MutIsoseq approach with five mutant lines susceptible to race CYR23,we rapid isolated a candidate gene for YrXZ encoding coiled-coil nucleotide-binding site leucine-rich repeat(CC-NBS-LRR)protein.Integrating cytological analysis,gene-based association analysis,transcriptomic profiling and virus-induced gene silencing(VIGS),we confirmed that the causal gene for YrXZ was indeed Yr9.This study demonstrated that multiple QTL with different effects contributed to the durable resistance in XZ9104.Understanding the molecular mechanisms and pathways involved in plant defense can inform future strategies for deploying resistance gene and engineering of genetic resistance against evolving diseases.展开更多
Stripe (yellow) rust caused by Puccinia striiformis f. sp. tritici occurs in almost allwheat-producing regions of the world. Severe countrywide epidemics in Chinahave caused substantial yield losses. Growing resistant...Stripe (yellow) rust caused by Puccinia striiformis f. sp. tritici occurs in almost allwheat-producing regions of the world. Severe countrywide epidemics in Chinahave caused substantial yield losses. Growing resistant cultivars is the beststrategy to control this disease but the pathogen can overcome resistance inwheat cultivars. The high variation in the virulence of the pathogen combinedwith the large areas of susceptible wheat cultivars enables the pathogenpopulation to increase rapidly and disperse over long distances under favorableenvironmental conditions, resulting in severe pandemics within croppingseasons. Current stripe rust control measures are based on many years ofresearch including the underlying epidemiology regarding year-to-year survivalof the pathogen, pathways of pathogen dispersal within seasons and years, therole of P. striiformis sexual hybridization, the use of resistance sources inbreeding programs, and year-round surveillance of national wheat crops that arepresent in different parts of the country throughout the year. All these strategiesdepend on accurate prediction of epidemics, more precise use of fungicides tomeet national requirements and better deployment of resistance genes. Newideas with potential application in sustainable protection of stripe rust includenegative regulatory gene editing, resistance gene overexpression and biologicalcontrol based on microbiomes.展开更多
基金funded by the National Natural Science Foundation of China(No.52278429)the Key R&D Program in Shaanxi Province(Nos.2023-ZDLGY-25,2025SF-YBXM-537)+1 种基金the Fundamental Research Funds for the Central Universities,CHD(No.300102315203)Transportation Science and Technology Project in Shaanxi Province(Nos.23-91K,24-14K,24-39K).
文摘The plateau environment not only affects the development of concrete's early strength but also damages its durability during its service life.This paper summarized and analyzed the impact of plateau environments on concrete’properties and proposed methods to improve the performance of concrete in plateau environment.The results indicated that low humidity and high evaporation rates in plateau regions inhibit the hydration of cement in concrete,leading to an increased content of micro-pores ranging from 500 to 1000 nm and raising the risk of early-stage cracking,thus reducing the impermeability of concrete.The low atmospheric pressure(AP)condition of 60 kPa decreases the entrained air content in concrete by over 20%,diminishes the pores under 200μm,and increases the average air-voids diameter and spacing factor,resulting in a decrease of more than 5%in the 28 d compressive strength of concrete.Consequently,the durability of concrete is compromised.Saponin and rosinbased air-entraining agents are recommended to improve the performance of concrete in plateau environments.Nanoparticles also aid in stabilizing bubbles in such conditions.Selecting low-heat specialty cements,increasing the amount of cement used,and extending the curing period are also vital measures to enhance the performance of plateau concrete.
文摘The objective of this review is to describe events in China and elsewhere that are related to the discovery, genetic identification, use, and ultimate break-down of a single wheat gene for resistance to stripe rust, namely Yr24/Yr26. In our retrospective analysis there was an early assumption of at least three genes at or near the locus, which caused an erroneous presumption of genetic diversity for resistance. It is an example of another boom and bust cycle in plant breeding with races virulent to Yr26(V26 races) now being the majority race group in the Chinese Pst population. We have attempted to present our story in a historical and personal context demonstrating research inputs from different national and international groups, as well as some significant contemporary side issues. It covers the period from the late 1980 s to 2017, during which significant rapid advances in the molecular biology of host: pathogen genetics occurred. We attempt to describe both successes and drawbacks in our work.
基金financially supported by the National Youth Foundation of China(31901494,31601306,and 31901869)the National Natural Science Foundation of China(31971890)+1 种基金supported by Young Elite Scientists Sponsorship Program of China Association for Science and Technology(2017QNRC001)the Natural Science Fund of Jiangsu Province,China(BK20161092)。
文摘Most modern wheat cultivars were selected on the basis of yield-related indices measured under optimal fertilizer and irrigation inputs.With climate change,land degradation and salinity caused by sea water encroachment,wheat is increasingly subjected to environmental stress.Moreover,expanding urbanization increasingly encroaches upon prime agricultural land in countries like China,and alternative cropping areas must be found.Some of these areas have moderate constraining factors,such as salinity.Therefore,it is important to investigate whether current genetic materials and breeding procedures are maintaining adequate variability to address future problems caused by abiotic stress.In this study,a panel of 307 wheat accessions,including local landraces,exotic cultivars used in Chinese breeding programs and Chinese cultivars released during different periods since1940,were subjected to a genome-wide association study to dissect the genetic basis of salinity tolerance.Both marker-based and pedigree-based kinship analyses revealed that favorable haplotypes were introduced in some exotic cultivars as well as a limited number of Chinese landraces from the 1940 s.However,improvements in salinity tolerance during modern breeding are not as obvious as that of yield.To broaden genetic diversity for increasing salt tolerance,there is a need to refocus attention on local landraces that have high degrees of salinity tolerance and carry rare favorable alleles that have not been exploited in breeding.
基金financially supported by the National Science Foundation for Young Scientists of China(31701421)the National Key Research and Development Program of China(2016YFE0108600)+2 种基金the China Agriculture Research System(CARS-3-1-11)the Genetically Modified Organisms Breeding Major Project(2016ZX08002001)the Key Project of Science and Technology of Tibetan Autonomous Region,China(XZ201702NB15)
文摘Wheat crops in China are constantly challenged by stripe rust. Deployment of cultivars with diverse resistances is the best strategy to control the disease. A recombinant inbred line(RIL) population derived from a cross between the resistant cultivar Chakwal 86 and susceptible landrace Mingxian 169 was studied in multiple environments to examine the underlying genetics and to identify quantitative trait loci(QTL) for stripe rust resistance.One hundred and twenty-eight RILs were genotyped with wheat 35 K SNP array and a genome-wide linkage map with 1480 polymorphic SNP markers, or bins, was constructed.Two major QTL on chromosomes 1BL and 3BS, and one minor QTL on 6BS had significant effects in reducing stripe rust severity. The QTL were validated using composite interval mapping(CIM) and inclusive composite interval mapping(ICIM). These methods explained59.0%–74.1% of the phenotype variation in disease response. The QTL on chromosome 1 BL was confirmed to be Yr29/Lr46 and the one on 3BS was the resistance allele identified in CIMMYT germplasm but was not Yr30/Sr2. The QTL on 6BS probably corresponded to previously known QTL. RILs with combined QTL were more resistant than those with single or no QTL. Kompetitive allele-specific PCR(KASP) assays for the QTL with largest effect QTL on chromosome 3BS were performed on a subset of RILs and 150 unrelated wheat lines. The QTL on 3BS with its linked KASP markers can be used in marker-assisted selection to improve stripe rust resistance in breeding programs.
基金financially the National Natural Science Foundation of China(31871611 and31971890)the National Science Foundation for Young Scientistsin China(31901494 and 31901869)+1 种基金International Cooperation and Exchange of the National Natural Science Foundation of China(31961143019)the Integrated Extension Project of Agricultural Science and Technology Innovation in Shaanxi Province(NYKJ-2021-YL(XN)15)。
文摘The development and deployment of diverse resistance sources in new wheat cultivars underpin the durable control of stripe rust.In the present study,two loci for adult plant resistance(APR),QYr SM155.1 and QYr SM155.2,were identified in the Chinese wheat breeding line Shaanmai 155.QYr SM155.1 was mapped to a 3.0-c M interval between the single-nucleotide polymorphism(SNP)markers AX-109583610 and AX-110907562 on chromosome arm 2 BL.QYr SM155.2 was mapped to a 2.1-c M interval flanked by the SNP markers AX-110378556 and AX-86173526 on chromosome arm 7 AS.A genome-wide association study was used to identify markers associated with APR in a panel of 411 spring wheat lines.Thirteen and 11 SNPs were significantly associated with QYr SM155.1 and QYr SM155.2,respectively,corresponding to physical intervals of 653.75–655.52 Mb on 2 BL and 81.63–83.93 Mb on7 AS.To characterize the haplotype variation and the distribution of these QTL,haplotype analysis was performed based on these SNPs in an independent panel of 1101 worldwide wheat accessions.Three major haplotypes(2 B_h1,2 B_h2,and 2 B_h3)for QYr SM155.1 and four major haplotypes(7 A_h1,7 A_h2,7 A_h3,and 7 A_h4)for QYr SM155.2 were identified.Accessions individually harboring QYr SM155.1_h1 and QYr SM155.2_h1 haplotypes and their combination displayed resistance.Additional assays of 1306 current Chinese cultivars and breeding lines using markers flanking QYr SM155.1 and QYr SM155.2 indicated that the resistance haplotypes of the two QTL were present in respectively 1.45%and 14.16%of lines.Increasing resistance haplotype frequencies at these two loci using marker-assisted selection should benefit wheat production in China.
基金financially supported by the National Key Research and Development Program of China (2022YFD1200900 and 2022YFD1200904)the Agricultural Science and Technology Innovation Program+1 种基金Fundamental Research Funds for Central NonProfit of Institute of Crop Sciences, CAASShijiazhuang S&T Project (232490022A and 232490432A)
文摘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.
基金supported by the National Key R&D Program of China(no.2022YFE0116200)the Key R&D Program of Qinghai Province(2022-NK-125)the Key R&D Program of Yangling Seed Industry Innovation Center(grant no.Ylzy-xm-01).
文摘Stay-green(SG)in wheat is a beneficial trait that increases yield and stress tolerance.However,conventional phenotyping techniques limited the understanding of its genetic basis.Spectral indices(SIs)as non-destructive tools to evaluate crop temporal senescence provide an alternative strategy.Here,we applied Sls to monitor the senescence dynamics of 565 diverse wheat accessions from anthesis to maturation stages over 2 field seasons.Four Sis(normalized difference vegetation index,green normalized difference vegetation index,normalized difference red edge index,and optimized soil-adjusted vegetation index)were normalized to develop relative stay-green scores(RSGS)as the SG indicators.An RSGS-based genome-wide association study identified 47 high-confidence quantitative trait loci(QTL)harboring 3,079 single-nucleotide polymorphisms associated with SG and 1,085 corresponding candidate genes.Among them,15 QTL overlapped or were adjacent to known SG-related QTL/genes,while the remaining QTL were novel.Notably,a set of favorable haplotypes of SG-related candidate genes such as TraesCS2A03G1081100,TracesCS6B03G0356400,and TracesCS2B03G1299500 are increasing following the Green Revolution,further validating the feasibility of the pipeline.This study provided a valuable reference for further quantitative SG and genetic research in diverse wheat panels.
基金supported by the National Key R&D Program of China(Grant No.2021YFD1401000)the National Natural Science Foundation of China(Grant Nos.32201745,32272088,32472103,31961143019,and 32421004)+1 种基金the Natural Science Basic Research Plan of Shaanxi Province,China(Grant Nos.2019JCW-18 and 2020JCW-16)the Yazhouwan National Laboratory Project(Grant No.2310JM01).
文摘Dear Editor,Wheat is one of the most important food crops.In recent years,factors such as global warming have led to the frequent occurrence of extreme weather,altering the epidemic patterns of crop diseases and pests and posing severe challenges to food security(Savary et al.2019).Wheat yellow rust(YR),also known as stripe rust,is caused by the biotrophic fungus Puccinia striiformis Westend f.sp.tritici(Pst)and remains one of the most devastating diseases threatening global wheat production(Chen 2020;Hovmoller et al.2023).
基金financially supported by the National Key R&D Program of China(2021YFD1200600)International Cooperation and Exchange of the National Natural Science Foundation of China(grant no.31961143019)+2 种基金the National Science Foundation for Young Scientists in China(grant no.32302377)the National Natural Science Foundation of China(grant nos.32272088 and 32372562)the Major Program of the National Natural Science Foundation of China(32293240).
文摘Single-nucleotide polymorphisms(SNPs)arewidely used asmolecularmarkers for constructing genetic linkage maps in wheat.Compared with available SNP-based genotyping platforms,a genotyping by target sequencing(GBTS)system with capture-in-solution(liquid chip)technology has become the favored genotyping technology because it is less demanding and more cost effective,flexible,and user-friendly.In this study,a new GenoBaits WheatSNP16K(GBW16K)GBTS array was designed using datasets generated by the wheat 660K SNP array and resequencing platforms in our previous studies.The GBW16K array contains 14868 target SNP regions that are evenly distributed across the wheat genome,and 37669 SNPs in these regions can be identified in a diversity panel consisting of 239wheat accessions from around theworld.Principal component and neighbor-joining analyses using the called SNPs are consistent with the pedigree information and geographic distributions or ecological environments of the accessions.For the GBW16K marker panel,the average genetic diversity among the 239 accessions is 0.270,which is sufficient for linkage map construction and preliminary mapping of targeted genes or quantitative trait loci(QTLs).A genetic linkage map,constructed using the GBW16K array-based genotyping of a recombinant inbred line population derived from a cross of the CIMMYT wheat line Yaco“S”and the Chinese landrace Mingxian169,enables the identification of Yr27,Yr30,and QYr.nwafu-2BL.4 for adult-plant resistance to stripe rust from Yaco“S”and of Yr18 from Mingxian169.QYr.nwafu-2BL.4 is different from any previously reported gene/QTL.Three haplotypes and six candidate genes have been identified for QYr.nwafu-2BL.4 on the basis of haplotype analysis,micro-collinearity,gene annotation,RNA sequencing,and SNP data.This array provides a new tool for wheat genetic analysis and breeding studies and for achieving durable control of wheat stripe rust.
基金supported by the National Key R&D Program of China(No.2022YFE0116200)the Key R&D Program of Qinghai Province(2022-NK-125)Key R&D Program of Yangling Seed Industry Innovation Center(grant no.Ylzy-xm-01).
文摘Repeated occurrences of extreme weather events,such as low temperatures,due to global warming present a serious risk to the safety of wheat production.Quantitative assessment of frost damage can facilitate the analysis of key genetic factors related to wheat tolerance to abiotic stress.We collected 491 wheat accessions and selected four image-based descriptors(BLUE band,RED band,NDVI,and GNDVI)to quantitatively assess their frost damage.Image descriptors can complement the visual estimation of frost damage.Combined with genome-wide association study(GWAS),a total of 107 quantitative trait loci(QTL)(r^(2) ranging from 0.75%to 9.48%)were identified,including the wellknown frost-resistant locus Frost Resistance(FR)-A1/Vernalization(VRN)-A1.Additionally,through quantitative gene expression data and mutation experience verification experiments,we identified two other frost tolerance candidate genes TraesCS2A03G1077800 and TraesCS5B03G1008500.Furthermore,when combined with genomic selection(GS),image-based descriptors can predict frost damage with high accuracy(r≤0.84).In conclusion,our research confirms the accuracy of image-based high-throughput acquisition of frost damage,thereby supplementing the exploration of the genetic structure of frost tolerance in wheat within complex field environments.
基金supported financially by National Key R&D Program of China(2021YFD1401000)Key Research and Development Program of Shaanxi(ProgramNo.2024NC2-GJHX-36)+1 种基金Innovation Capability Support Program of Shaanxi(Program No.2023-CX-TD-56)China Agriculture Research System(CARS-3).
文摘The fungus Puccinia striiformis f.sp.tritici(Pst)is the causal agent of wheat stripe rust which constitutes a major limitation to wheat production.Cloning and applying disease-resistant genes are considered as an effective solution.Chinese wheat cultivar Xingzi 9104(XZ9104)has exhibited durable resistance across multiple environments since its release.Through quantitative trait loci(QTL)analysis,eight QTL were found on chromosome arms 1BS,1BL,2AL,2BL,3BS,4BL,5BL and 7BL.YrXZ identified as 1RS.1BL translocation conferred race-specific all-stage resistance to Pst race CYR23.QYrxz.nwafu-1BL.6 and QYrxz.nwafu-3BS.7 were considered as the adult plant resistance genes Yr29 and Yr30,respectively.Notably,QYrxz.nwafu-2BL.5 accounted for 15.75-47.63%of the phenotypic variation across diverse environments and its pyramiding with Yr29 and Yr30 can confer high level of resistance.Other QTL were environment-dependent with minor effects.To clone the above resistance genes,we created a population of over 2,000 M5 mutants in XZ9104 using ethylmethane sulfonate(EMS)mutagenesis and screened various types of susceptible mutants.Using the MutIsoseq approach with five mutant lines susceptible to race CYR23,we rapid isolated a candidate gene for YrXZ encoding coiled-coil nucleotide-binding site leucine-rich repeat(CC-NBS-LRR)protein.Integrating cytological analysis,gene-based association analysis,transcriptomic profiling and virus-induced gene silencing(VIGS),we confirmed that the causal gene for YrXZ was indeed Yr9.This study demonstrated that multiple QTL with different effects contributed to the durable resistance in XZ9104.Understanding the molecular mechanisms and pathways involved in plant defense can inform future strategies for deploying resistance gene and engineering of genetic resistance against evolving diseases.
基金The authors acknowledge support from the National Natural Science Foundation of China(31620103913)the“111 Project”from the Ministry of Education of China(BP0719026)the Natural Science Basic Research Plan in Shaanxi Province of China(2019JCW-18).The authors are grateful to Professor R.A.McIntosh,Plant Breeding Institute,University of Sydney,Australia,for critical review of this manuscript.
文摘Stripe (yellow) rust caused by Puccinia striiformis f. sp. tritici occurs in almost allwheat-producing regions of the world. Severe countrywide epidemics in Chinahave caused substantial yield losses. Growing resistant cultivars is the beststrategy to control this disease but the pathogen can overcome resistance inwheat cultivars. The high variation in the virulence of the pathogen combinedwith the large areas of susceptible wheat cultivars enables the pathogenpopulation to increase rapidly and disperse over long distances under favorableenvironmental conditions, resulting in severe pandemics within croppingseasons. Current stripe rust control measures are based on many years ofresearch including the underlying epidemiology regarding year-to-year survivalof the pathogen, pathways of pathogen dispersal within seasons and years, therole of P. striiformis sexual hybridization, the use of resistance sources inbreeding programs, and year-round surveillance of national wheat crops that arepresent in different parts of the country throughout the year. All these strategiesdepend on accurate prediction of epidemics, more precise use of fungicides tomeet national requirements and better deployment of resistance genes. Newideas with potential application in sustainable protection of stripe rust includenegative regulatory gene editing, resistance gene overexpression and biologicalcontrol based on microbiomes.
