Fusarium crown rot(FCR),predominantly caused by Fusarium pseudograminearum,has been listed as a Category Ⅱ disease in six provinces of China,posing a significant threat to wheat production.The phenylpyrrole fungicide...Fusarium crown rot(FCR),predominantly caused by Fusarium pseudograminearum,has been listed as a Category Ⅱ disease in six provinces of China,posing a significant threat to wheat production.The phenylpyrrole fungicide fludioxonil is a key agent for FCR control.Previous studies indicated that resistance to fludioxonil in F.pseudograminearum is primarily associated with altered expression levels of the FpOS1 gene,which encodes a hybrid histidine kinase.However,the roles of mutations in other FpOS genes and the molecular interactions between FpOS proteins and fludioxonil remain elusive.To address these gaps,we generated 16 fludioxonil-resistant mutants with heritable resistance traits by in vitro selection of four sensitive F.pseudograminearum isolates.These mutants exhibited high resistance levels,with resistance factors(RF)ranging from 633.73 to 8617.07.Compared to their parental isolates,the resistant mutants showed significantly reduced mycelial growth rate,sporulation capacity,and pathogenicity.They were also more sensitive to ionic,osmotic,and oxidative stresses and displayed compromised cell wall and membrane integrity.Fludioxonil demonstrated no cross-resistance with tebuconazole or pydiflumetofen;however,it exhibited weak positive crossresistance to pyraclostrobin and moderate positive cross-resistance to iprodione.Fludioxonil treatment significantly promoted glycerol synthesis and inhibited deoxynivalenol(DON)production in parental isolates,whereas these regulatory effects were markedly attenuated in the resistant mutants.Mutation analysis identified mutation sites in FpOS1,FpOS4,and FpOS5 genes,with a lower mutation frequency in FpOS1 and no mutations detected in FpOS2.Molecular docking indicated that amino acid substitutions in FpOS4 and FpOS5 significantly reduced the binding affinity of fludioxonil to these target proteins.In conclusion,F.pseudograminearum poses a moderate risk of resistance to fludioxonil.Point mutations in FpOS4 and FpOS5 genes emerge as key molecular drivers of resistance,likely by diminishing the binding affinity between the fungicide and its proteins.This study clarifies the molecular basis of fludioxonil resistance in F.pseudograminearum and provides a scientific rationale for the judicious use of this fungicide in managing FCR.展开更多
Fusarium head blight(FHB),mainly caused by fungus Fusarium graminearum,is a devastating wheat disease worldwide,leading to reduced yield production and compromised grain quality due to contamination by mycotoxins,such...Fusarium head blight(FHB),mainly caused by fungus Fusarium graminearum,is a devastating wheat disease worldwide,leading to reduced yield production and compromised grain quality due to contamination by mycotoxins,such as deoxynivalenol(DON).Manipulating the specific gene expression in microorganisms through RNA interference(RNAi)presents an opportunity for new-generation double-stranded RNA(dsRNA)-based formulations to combat a large number of plant diseases.Here,we applied both spray-induced gene silencing(SIGS)and host-induced gene silencing(HIGS)to target five virulence-related and DON-synthesized genes in F.graminearum,including protein kinase gene Gpmk1,zinc finger protein gene Fg Chy1,transcription factor Fg SR,DON synthesis gene TRI5 and the cell-end marker protein gene Fg Tea A,aiming to effectively control FHB in wheat.Direct spraying of individual or combined small interfering RNA(siRNAs)from the fungus showed reduced expression of target genes and suppressed pathogenic symptoms during F.graminearum infection in wheat leaves,with the combination of all five siRNAs demonstrating superior resistance.Furthermore,we generated transgenic wheat lines expressing chimeric RNAi cassettes targeting these five genes,and two independent lines exhibited strong resistance to FHB and Fusarium crown rot,and the reduced DON accumulation.Notably,the HIGS transgenic lines did not adversely impact plant growth and yield traits.Collectively,our findings support that SIGS and HIGS represent effective strategies targeting key pathogenic genes for bolstering disease resistance in crops.展开更多
In recent years,an unusual wilt disease affecting Pyrus pyrifolia has been observed in various regions of Jiangsu,China.This disease originates from the roots and progresses with distinctive browning patterns along va...In recent years,an unusual wilt disease affecting Pyrus pyrifolia has been observed in various regions of Jiangsu,China.This disease originates from the roots and progresses with distinctive browning patterns along vascular tissues,even extending over two meters above the ground.These symptoms set it apart from recognized pear diseases and typically lead to the death of affected trees within the same or the following year.Furthermore,this disease exhibits a tendency to spread to neighboring trees even after the removal of affected trees,presenting a substantial threat to pear production.To ascertain the causative agent,the present study encompassed pathogen isolation,morphological and molecular identification,as well as validation experiments adhering to Koch's postulates.The fungal isolates obtained were identified as Fusarium cugenangense based on characteristics of the colonies and conidia,in addition to a phylogenetic analysis using DNA sequences of the translation elongation factor 1-alpha(tef1),calmodulin(Ca M),and RNA polymerase second largest subunit(rpb2)genes.Pathogenicity of the isolated F.cugenangense on pear was confirmed by artificial inoculation.By introducing GFP-labeled pathogens into the roots,colonization in stem and leaf tissues was observed via fluorescence microscopy and transmission electron microscopy.Furthermore,these pathogens were successfully reisolated from stems and foliage,conclusively providing evidence of systemic infection within the pear plants.To the best of our knowledge,this is the first report of F.cugenangense causing pear wilt disease in China.展开更多
Root rot is a prevalent soil-borne fungal disease in citrus.Citron C-05(Citrus medica)stands out as a germplasm within Citrus spp.due to its complete resistance to citrus canker and favorable characteristics such as s...Root rot is a prevalent soil-borne fungal disease in citrus.Citron C-05(Citrus medica)stands out as a germplasm within Citrus spp.due to its complete resistance to citrus canker and favorable characteristics such as single embryo and easy rooting.However,Citron C-05 was found to be highly susceptible to root rot during cultivation,with the specific pathogens previously unknown.In this study,four candidate fungal species were isolated from Citron C-05 roots.Sequence analysis of ITS,EF-1a,RPB1,and RPB2 identified two Fusarium solani strains,Rr-2 and Rr-4,as the candidates causing root rot in Citron C-05.Resistance tests showed these two pathogens increased root damage rate from 10.30%to 35.69%in Citron C-05,sour orange(Citrus aurantium),sweet orange(Citrus sinensis)and pummelo(Citrus grandis).F.solani exhibited the weak pathogenicity towards trifoliate orange(Poncirus trifoliata).DAB staining revealed none of reddish-brown precipitation in the four susceptible citrus germplasm after infection with F.solani,while trifoliate orange exhibited significant H2O2 accumulation.Trypan blue staining indicated increased cell death in the four susceptible citrus germplasm following infection with these two pathogens but not in trifoliate orange.These findings provide a comprehensive understanding of citrus root rot and support future research on the mechanisms of root rot resistance in citrus.展开更多
Fusarium ear rot(FER),caused by Fusarium verticillioides,is a destructive fungal disease of maize.FER resistance is a complex,quantitatively inherited trait controlled by multiple minor-effect genes.In this study,we e...Fusarium ear rot(FER),caused by Fusarium verticillioides,is a destructive fungal disease of maize.FER resistance is a complex,quantitatively inherited trait controlled by multiple minor-effect genes.In this study,we employed two recombinant inbred line(RIL)populations with the common resistant parental line CML304 to identify FER-resistance loci.Initial QTL analysis identified 23 FER-resistance QTL,each explaining 5.21%-30.51%of the total phenotypic variation.Notably,one major QTL,qRfv2,on chromosome 2 was repeatedly detected,accounting for 11.92%-30.51%of the total phenotypic variation.qRfv2 was fine mapped to an interval of 1.01 Mb,flanked by the markers IDP8 and IDP10.qRfv2 is a semidominant resistance gene that could reduce the disease severity index(DSI)by 12.4%-20%,suggesting its potential for enhancing FER resistance in maize.Transcriptome analysis showed that 22 of the 28 annotated functional genes in the qRfv2 region displayed differential expression between parental lines in response to FER.One of the candidate genes,ZmLOX6,was validated to presumably provide a positive effect on FER resistance.Our study provides a basis for the potential cloning and application of FER resistance genes in maize breeding.展开更多
Fusarium head blight(FHB)is a serious fungal disease that affect small grain cereals,causing significant wheat(Triticum aestivum L.)yield and quality losses globally.Breeding disease-resistant wheat varieties is key t...Fusarium head blight(FHB)is a serious fungal disease that affect small grain cereals,causing significant wheat(Triticum aestivum L.)yield and quality losses globally.Breeding disease-resistant wheat varieties is key to address FHB-related challenges,but its progress is delayed by traditional methods due to the small-scale,laborious and relatively subjective nature of manual assessment.This study presents a new approach that combines ultralow-altitude drone phenotyping with an optimized You Only Look Once(YOLO)model to examine FHB in wheat,enabling us to perform large-scale and automated symptomatic analysis of this disease.We first established an Open FHB(OFHB)training dataset,consisting of 4867 diseased and 106,801 healthy spikes collected from 132 commercial breeding lines during FHB progression.Then,a deep learning model called YOLOv8-WFD was trained for detecting healthy and diseased spikes,followed by an adaptive Excess Green method to identify symptomatic regions and thus FHBrelated traits on spikes.To study resistance levels,we employed an unsupervised SHapley Additive exPlanations(SHAP)method to pinpoint key traits between 10 and 20 d after inoculation(DAIs),resulting in the classification of 423 varieties trialed during the 2023–2024 growing seasons into four resistance levels(i.e.,highly and moderately susceptible,and moderately and highly resistant),which were highly correlated with field specialists’evaluations.Finally,we derived disease developmental curves based on measures of key traits during 10–20 DAI,quantifying varietal disease progression patterns over time.To our knowledge,this work represents a significant advancement in large-scale disease phenotyping and automated analysis of FHB in wheat,providing a valuable toolkit for breeders and plant researchers to assess resistance levels,select disease-resistant varieties,and understand dynamics of the fungal disease.展开更多
Fusarium head blight(FHB),mainly caused by Fusarium graminearum,is one of the most devastating diseases of wheat worldwide.Identification and validation of major quantitative trait loci(QTLs)for FHB resistance without...Fusarium head blight(FHB),mainly caused by Fusarium graminearum,is one of the most devastating diseases of wheat worldwide.Identification and validation of major quantitative trait loci(QTLs)for FHB resistance without negative effects on agronomic traits is critical to success in breeding FHB-resistant cultivars.In this study,a stable major QTL on chromosome arm 2DL was identified by evaluating a recombinant inbred line(RIL)population derived from Shi4185×Shijiazhuang 8 in both field and greenhouse experiments.QTL mapping and pedigree analyses indicated that the 2DL QTL is the same as QFhb-2DL previously identified in Ji5265;therefore,it was designated Fhb9.Four kompetitive amplicon sequence polymorphism(KASP)markers were developed based on exome capture sequencing data to enhance marker density in the Fhb9 region,and it was delimited to an interval between single nucleotide polymorphism(SNP)markers KASP-12056(533.8 Mb)and KASP-525(525.9 Mb)explained 26.0-30.1%of the phenotypic variation.Analysis of the geographic distribution of the Fhb9 resistance allele suggests that it originated from the Huang-Huai winter wheat region in China.The very low frequency of Fhb9 in modern Chinese cultivars reveals that it has not been widely deployed in breeding programs.Field and greenhouse evaluations of yield-related traits in near-isogenic lines(NILs)contrasting in Fhb9 alleles reveal that the Fhb9 resistance allele have no adverse effects on these traits.Fhb9 showed an additive effect on enhancing FHB resistance with Fhb1.Therefore,Fhb9 is a valuable major QTL for improving FHB resistance in wheat,and the near-diagnostic markers developed in this study will facilitate its deployment in wheat breeding programs.展开更多
Yellow rust(Puccinia striiformis f.sp.Tritici,YR)and fusarium head blight(Fusarium graminearum,FHB)are the two main diseases affecting wheat in the main grain-producing areas of East China,which is common for the two ...Yellow rust(Puccinia striiformis f.sp.Tritici,YR)and fusarium head blight(Fusarium graminearum,FHB)are the two main diseases affecting wheat in the main grain-producing areas of East China,which is common for the two diseases to appear simultaneously in some main production areas.It is necessary to discriminate wheat YR and FHB at the regional scale to accurately locate the disease in space,conduct detailed disease severity monitoring,and scientific control.Four images on different dates were acquired from Sentinel-2,Landsat-8,and Gaofen-1 during the critical period of winter wheat,and 22 remote sensing features that characterize the wheat growth status were then calculated.Meanwhile,6 meteorological parameters that reflect the wheat phenological information were also obtained by combining the site meteorological data and spatial interpolation technology.Then,the principal components(PCs)of comprehensive remote sensing and meteorological features were extracted with principal component analysis(PCA).The PCs-based discrimination models were established to map YR and FHB damage using the random forest(RF)and backpropagation neural network(BPNN).The models’performance was verified based on the disease field truth data(57 plots during the filling period)and 5-fold cross-validation.The results revealed that the PCs obtained after PCA dimensionality reduction outperformed the initial features(IFs)from remote sensing and meteorology in discriminating between the two diseases.Compared to the IFs,the average area under the curve for both micro-average and macro-average ROC curves increased by 0.07 in the PCs-based RF models and increased by 0.16 and 0.13,respectively,in the PCs-based BPNN models.Notably,the PCs-based BPNN discrimination model emerged as the most effective,achieving an overall accuracy of 83.9%.Our proposed discrimination model for wheat YR and FHB,coupled with multi-source remote sensing images and meteorological data,overcomes the limitations of a single-sensor and single-phase remote sensing information in multiple stress discrimination in cloudy and rainy areas.It performs well in revealing the damage spatial distribution of the two diseases at a regional scale,providing a basis for detailed disease severity monitoring,and scientific prevention and control.展开更多
基金Supported by Funding from the Henan Provincial Scientific and Technological Breakthrough Project(No.242102111113).
文摘Fusarium crown rot(FCR),predominantly caused by Fusarium pseudograminearum,has been listed as a Category Ⅱ disease in six provinces of China,posing a significant threat to wheat production.The phenylpyrrole fungicide fludioxonil is a key agent for FCR control.Previous studies indicated that resistance to fludioxonil in F.pseudograminearum is primarily associated with altered expression levels of the FpOS1 gene,which encodes a hybrid histidine kinase.However,the roles of mutations in other FpOS genes and the molecular interactions between FpOS proteins and fludioxonil remain elusive.To address these gaps,we generated 16 fludioxonil-resistant mutants with heritable resistance traits by in vitro selection of four sensitive F.pseudograminearum isolates.These mutants exhibited high resistance levels,with resistance factors(RF)ranging from 633.73 to 8617.07.Compared to their parental isolates,the resistant mutants showed significantly reduced mycelial growth rate,sporulation capacity,and pathogenicity.They were also more sensitive to ionic,osmotic,and oxidative stresses and displayed compromised cell wall and membrane integrity.Fludioxonil demonstrated no cross-resistance with tebuconazole or pydiflumetofen;however,it exhibited weak positive crossresistance to pyraclostrobin and moderate positive cross-resistance to iprodione.Fludioxonil treatment significantly promoted glycerol synthesis and inhibited deoxynivalenol(DON)production in parental isolates,whereas these regulatory effects were markedly attenuated in the resistant mutants.Mutation analysis identified mutation sites in FpOS1,FpOS4,and FpOS5 genes,with a lower mutation frequency in FpOS1 and no mutations detected in FpOS2.Molecular docking indicated that amino acid substitutions in FpOS4 and FpOS5 significantly reduced the binding affinity of fludioxonil to these target proteins.In conclusion,F.pseudograminearum poses a moderate risk of resistance to fludioxonil.Point mutations in FpOS4 and FpOS5 genes emerge as key molecular drivers of resistance,likely by diminishing the binding affinity between the fungicide and its proteins.This study clarifies the molecular basis of fludioxonil resistance in F.pseudograminearum and provides a scientific rationale for the judicious use of this fungicide in managing FCR.
基金financially supported by the National Key R&D Program of China(2022YFD1400105)the Jiangsu Agricultural Science and Technology Innovation Fund(CX(22)2005)+3 种基金the Jiangsu Key R&D Plan(Modern Agriculture),China(BE2022346)the China Agricultural Research System Program(CARS-03)the National Science Fund for Excellent Young Scholars(Overseas),Chinathe Start-Up Grant from Nanjing Agricultural University,China。
文摘Fusarium head blight(FHB),mainly caused by fungus Fusarium graminearum,is a devastating wheat disease worldwide,leading to reduced yield production and compromised grain quality due to contamination by mycotoxins,such as deoxynivalenol(DON).Manipulating the specific gene expression in microorganisms through RNA interference(RNAi)presents an opportunity for new-generation double-stranded RNA(dsRNA)-based formulations to combat a large number of plant diseases.Here,we applied both spray-induced gene silencing(SIGS)and host-induced gene silencing(HIGS)to target five virulence-related and DON-synthesized genes in F.graminearum,including protein kinase gene Gpmk1,zinc finger protein gene Fg Chy1,transcription factor Fg SR,DON synthesis gene TRI5 and the cell-end marker protein gene Fg Tea A,aiming to effectively control FHB in wheat.Direct spraying of individual or combined small interfering RNA(siRNAs)from the fungus showed reduced expression of target genes and suppressed pathogenic symptoms during F.graminearum infection in wheat leaves,with the combination of all five siRNAs demonstrating superior resistance.Furthermore,we generated transgenic wheat lines expressing chimeric RNAi cassettes targeting these five genes,and two independent lines exhibited strong resistance to FHB and Fusarium crown rot,and the reduced DON accumulation.Notably,the HIGS transgenic lines did not adversely impact plant growth and yield traits.Collectively,our findings support that SIGS and HIGS represent effective strategies targeting key pathogenic genes for bolstering disease resistance in crops.
基金supported by the Jiangsu Agricultural Science and Technology Innovation Fund,China(CX(23)1011)the Earmarked Fund for China Agriculture Research System(CARS-28)+3 种基金the National Natural Science Foundation of China(31901837)the China Postdoctoral Science Foundation(2020M671389)the Basal Research Fund for the Jiangsu Academy of Agricultural Sciences,China(ZX(23)3016)the Yafu Technology Service Project,China(KF(23)1106)。
文摘In recent years,an unusual wilt disease affecting Pyrus pyrifolia has been observed in various regions of Jiangsu,China.This disease originates from the roots and progresses with distinctive browning patterns along vascular tissues,even extending over two meters above the ground.These symptoms set it apart from recognized pear diseases and typically lead to the death of affected trees within the same or the following year.Furthermore,this disease exhibits a tendency to spread to neighboring trees even after the removal of affected trees,presenting a substantial threat to pear production.To ascertain the causative agent,the present study encompassed pathogen isolation,morphological and molecular identification,as well as validation experiments adhering to Koch's postulates.The fungal isolates obtained were identified as Fusarium cugenangense based on characteristics of the colonies and conidia,in addition to a phylogenetic analysis using DNA sequences of the translation elongation factor 1-alpha(tef1),calmodulin(Ca M),and RNA polymerase second largest subunit(rpb2)genes.Pathogenicity of the isolated F.cugenangense on pear was confirmed by artificial inoculation.By introducing GFP-labeled pathogens into the roots,colonization in stem and leaf tissues was observed via fluorescence microscopy and transmission electron microscopy.Furthermore,these pathogens were successfully reisolated from stems and foliage,conclusively providing evidence of systemic infection within the pear plants.To the best of our knowledge,this is the first report of F.cugenangense causing pear wilt disease in China.
基金supported by Joint Funds of the National Natural Science Foundation of China(Grant No.U21A20228).
文摘Root rot is a prevalent soil-borne fungal disease in citrus.Citron C-05(Citrus medica)stands out as a germplasm within Citrus spp.due to its complete resistance to citrus canker and favorable characteristics such as single embryo and easy rooting.However,Citron C-05 was found to be highly susceptible to root rot during cultivation,with the specific pathogens previously unknown.In this study,four candidate fungal species were isolated from Citron C-05 roots.Sequence analysis of ITS,EF-1a,RPB1,and RPB2 identified two Fusarium solani strains,Rr-2 and Rr-4,as the candidates causing root rot in Citron C-05.Resistance tests showed these two pathogens increased root damage rate from 10.30%to 35.69%in Citron C-05,sour orange(Citrus aurantium),sweet orange(Citrus sinensis)and pummelo(Citrus grandis).F.solani exhibited the weak pathogenicity towards trifoliate orange(Poncirus trifoliata).DAB staining revealed none of reddish-brown precipitation in the four susceptible citrus germplasm after infection with F.solani,while trifoliate orange exhibited significant H2O2 accumulation.Trypan blue staining indicated increased cell death in the four susceptible citrus germplasm following infection with these two pathogens but not in trifoliate orange.These findings provide a comprehensive understanding of citrus root rot and support future research on the mechanisms of root rot resistance in citrus.
基金financially funded by the National Natural Science Foundation of China(U2004205)the China Agricultural University-Syngenta Project.
文摘Fusarium ear rot(FER),caused by Fusarium verticillioides,is a destructive fungal disease of maize.FER resistance is a complex,quantitatively inherited trait controlled by multiple minor-effect genes.In this study,we employed two recombinant inbred line(RIL)populations with the common resistant parental line CML304 to identify FER-resistance loci.Initial QTL analysis identified 23 FER-resistance QTL,each explaining 5.21%-30.51%of the total phenotypic variation.Notably,one major QTL,qRfv2,on chromosome 2 was repeatedly detected,accounting for 11.92%-30.51%of the total phenotypic variation.qRfv2 was fine mapped to an interval of 1.01 Mb,flanked by the markers IDP8 and IDP10.qRfv2 is a semidominant resistance gene that could reduce the disease severity index(DSI)by 12.4%-20%,suggesting its potential for enhancing FER resistance in maize.Transcriptome analysis showed that 22 of the 28 annotated functional genes in the qRfv2 region displayed differential expression between parental lines in response to FER.One of the candidate genes,ZmLOX6,was validated to presumably provide a positive effect on FER resistance.Our study provides a basis for the potential cloning and application of FER resistance genes in maize breeding.
基金supported by the Biological Breeding-National Science and Technology Major Project(2023ZD04025 to Xiu’e Wang)the Seed Industry Revitalization Project of Jiangsu Province(JBGS(2021)006 to Xiu’e Wang)+3 种基金the National Natural Science Foundation of China(32070400 to Ji Zhou)Ji Zhou,Robert Jackson,and Greg Deakin were partially supported by the Allan&Gill Gray Foundation’Sustainable Productivity for Crop Improvement(G118688 to the University of Cambridge and Q-20-0370 to NIAB)Ji Zhou was supported by the United Kingdom Research and Innovation’s(UKRI)Biotechnology and Bio logical Sciences Research Council(BBSRC)AI in Bioscience Grant(BB/Y513969/1 to Ji Zhou)The UK-China research activities were supported by the BBSRC’s International Partnership Grant(BB/Y514081/1 to NIAB)
文摘Fusarium head blight(FHB)is a serious fungal disease that affect small grain cereals,causing significant wheat(Triticum aestivum L.)yield and quality losses globally.Breeding disease-resistant wheat varieties is key to address FHB-related challenges,but its progress is delayed by traditional methods due to the small-scale,laborious and relatively subjective nature of manual assessment.This study presents a new approach that combines ultralow-altitude drone phenotyping with an optimized You Only Look Once(YOLO)model to examine FHB in wheat,enabling us to perform large-scale and automated symptomatic analysis of this disease.We first established an Open FHB(OFHB)training dataset,consisting of 4867 diseased and 106,801 healthy spikes collected from 132 commercial breeding lines during FHB progression.Then,a deep learning model called YOLOv8-WFD was trained for detecting healthy and diseased spikes,followed by an adaptive Excess Green method to identify symptomatic regions and thus FHBrelated traits on spikes.To study resistance levels,we employed an unsupervised SHapley Additive exPlanations(SHAP)method to pinpoint key traits between 10 and 20 d after inoculation(DAIs),resulting in the classification of 423 varieties trialed during the 2023–2024 growing seasons into four resistance levels(i.e.,highly and moderately susceptible,and moderately and highly resistant),which were highly correlated with field specialists’evaluations.Finally,we derived disease developmental curves based on measures of key traits during 10–20 DAI,quantifying varietal disease progression patterns over time.To our knowledge,this work represents a significant advancement in large-scale disease phenotyping and automated analysis of FHB in wheat,providing a valuable toolkit for breeders and plant researchers to assess resistance levels,select disease-resistant varieties,and understand dynamics of the fungal disease.
基金supported by the National Key Research and Development Program of China(2022YFD1201502)partially funded by the Talent Funds of China Agricultural University(2021RC009)the US Wheat and Barley Scab Initiative.
文摘Fusarium head blight(FHB),mainly caused by Fusarium graminearum,is one of the most devastating diseases of wheat worldwide.Identification and validation of major quantitative trait loci(QTLs)for FHB resistance without negative effects on agronomic traits is critical to success in breeding FHB-resistant cultivars.In this study,a stable major QTL on chromosome arm 2DL was identified by evaluating a recombinant inbred line(RIL)population derived from Shi4185×Shijiazhuang 8 in both field and greenhouse experiments.QTL mapping and pedigree analyses indicated that the 2DL QTL is the same as QFhb-2DL previously identified in Ji5265;therefore,it was designated Fhb9.Four kompetitive amplicon sequence polymorphism(KASP)markers were developed based on exome capture sequencing data to enhance marker density in the Fhb9 region,and it was delimited to an interval between single nucleotide polymorphism(SNP)markers KASP-12056(533.8 Mb)and KASP-525(525.9 Mb)explained 26.0-30.1%of the phenotypic variation.Analysis of the geographic distribution of the Fhb9 resistance allele suggests that it originated from the Huang-Huai winter wheat region in China.The very low frequency of Fhb9 in modern Chinese cultivars reveals that it has not been widely deployed in breeding programs.Field and greenhouse evaluations of yield-related traits in near-isogenic lines(NILs)contrasting in Fhb9 alleles reveal that the Fhb9 resistance allele have no adverse effects on these traits.Fhb9 showed an additive effect on enhancing FHB resistance with Fhb1.Therefore,Fhb9 is a valuable major QTL for improving FHB resistance in wheat,and the near-diagnostic markers developed in this study will facilitate its deployment in wheat breeding programs.
基金supported by National Key R&D Program of China(2022YFD2000100)National Natural Science Foundation of China(42401400)Zhejiang Provincial Key Research and Development Program(2023C02018).
文摘Yellow rust(Puccinia striiformis f.sp.Tritici,YR)and fusarium head blight(Fusarium graminearum,FHB)are the two main diseases affecting wheat in the main grain-producing areas of East China,which is common for the two diseases to appear simultaneously in some main production areas.It is necessary to discriminate wheat YR and FHB at the regional scale to accurately locate the disease in space,conduct detailed disease severity monitoring,and scientific control.Four images on different dates were acquired from Sentinel-2,Landsat-8,and Gaofen-1 during the critical period of winter wheat,and 22 remote sensing features that characterize the wheat growth status were then calculated.Meanwhile,6 meteorological parameters that reflect the wheat phenological information were also obtained by combining the site meteorological data and spatial interpolation technology.Then,the principal components(PCs)of comprehensive remote sensing and meteorological features were extracted with principal component analysis(PCA).The PCs-based discrimination models were established to map YR and FHB damage using the random forest(RF)and backpropagation neural network(BPNN).The models’performance was verified based on the disease field truth data(57 plots during the filling period)and 5-fold cross-validation.The results revealed that the PCs obtained after PCA dimensionality reduction outperformed the initial features(IFs)from remote sensing and meteorology in discriminating between the two diseases.Compared to the IFs,the average area under the curve for both micro-average and macro-average ROC curves increased by 0.07 in the PCs-based RF models and increased by 0.16 and 0.13,respectively,in the PCs-based BPNN models.Notably,the PCs-based BPNN discrimination model emerged as the most effective,achieving an overall accuracy of 83.9%.Our proposed discrimination model for wheat YR and FHB,coupled with multi-source remote sensing images and meteorological data,overcomes the limitations of a single-sensor and single-phase remote sensing information in multiple stress discrimination in cloudy and rainy areas.It performs well in revealing the damage spatial distribution of the two diseases at a regional scale,providing a basis for detailed disease severity monitoring,and scientific prevention and control.
