Peanut(Arachis hypogaea),which is widely cultivated across the world,provides high-quality vegetable oil,protein,dietary fiber,minerals,and vitamins for humans.However,in field conditions,the peanut is easily affected...Peanut(Arachis hypogaea),which is widely cultivated across the world,provides high-quality vegetable oil,protein,dietary fiber,minerals,and vitamins for humans.However,in field conditions,the peanut is easily affected by various biotic and abiotic stresses.Diplodia gossypina is the dominant pathogen causing severe collar rot on peanuts.To dissect the pathogenic mechanism of D.gossypina,genome sequencing analysis was performed by using the D.gossypina strain A20_4.The sequencing data showed that the genome assembly size of D.gossypina A20_4 is 43.03 Mb with a GC content of 54.91%.The de novo assembly identified a total of 10,745 genes,containing 41,526 coding sequences and 2.20%of repeat sequences,of which 6,461 genes(60.13%)were annotated using BlastP from GO annotation,3,245 genes(30.20%)and 3,093 genes(28.79%)were annotated from KOG and KEGG annotations,respectively.Meanwhile,the secreted proteins and effectors in 10,745 protein sequences encoded by the whole genome of D.gossypina A20_4 were analyzed,and the results showed that there are 790 secreted protein genes including 220 carbohydrate-active enzymes and 224 potential effector proteins.The functions of 222 potential effector proteins can be annotated by PHI-base.According to the annotation results,12 key pathogenic factors were identified in D.gossypina A20_4.Moreover,a serine/threonine protein kinase SNF1 gene required for autophagy process was identified and analyzed.Deciphering the whole genome of D.gossypina A20_4 provides us with novel insights into understanding evolution,pathogenic molecular mechanism,host-pathogen interaction,and many other complexities of the pathogen.展开更多
Bacterial soft rot(BSR)caused by Pectobacterium carotovorum subsp.brasiliense(Pcb)is a serious bacterial disease which negatively impact yield and quality in cucumber.However,the genetic mechanism of BSR resistance in...Bacterial soft rot(BSR)caused by Pectobacterium carotovorum subsp.brasiliense(Pcb)is a serious bacterial disease which negatively impact yield and quality in cucumber.However,the genetic mechanism of BSR resistance in cucumber has not been reported.Here,we investigated the BSR resistance of 119 cucumber core germplasm worldwide at the seedling stage and identified 26 accessions highly resistant to BSR.A total of 1642740 single-nucleotide polymorphisms(SNPs)were used to conduct GWAS,and five loci associated with BSR resistance were detected on four chromosomes:gBSR2.1,gBSR2.2,gBSR3.1,gBSR4.1 and gBSR5.1.Based on haplotype analysis,sequence polymorphisms,functional annotation and qRT-PCR analysis,six candidate genes were identified within the five loci.CsaV3_2G014450,CsaV3_2G014490,CsaV3_2G016000,CsaV3_3G000850,CsaV3_4G033150,and CsaV3_5G000390 each had nonsynonymous SNPs,and were significantly up-regulated in the resistant genotypes after inoculation.And CsaV3_5G000390 in the susceptible genotype was significantly up-regulated after inoculation.The identification of these candidate genes lays a foundation for understanding the genetic mechanism of BSR resistance in cucumber.Generally,our study mined genes associated with BSR resistance in cucumber seedlings and will assist the breeding of BSR-resistant cucumber cultivars.展开更多
Pythium stalk rot(PSR)is a destructive disease of maize,severely affecting yield and grain quality.The identification of quantitative trait loci(QTL)or genes for resistance to PSR forms the basis of diseaseresistant h...Pythium stalk rot(PSR)is a destructive disease of maize,severely affecting yield and grain quality.The identification of quantitative trait loci(QTL)or genes for resistance to PSR forms the basis of diseaseresistant hybrids breeding.In this study,a major QTL,Resistance to Pythium stalk rot 1(RPSR1),was identified from a set of recombinant inbred lines derived from MS71 and POP.Using a recombinant progeny testing strategy,RPSR1 was fine-mapped in a 472 kb interval.Through candidate gene expression,gene knock-down and knock-out studies,a leucine-rich repeat receptor-like kinase gene,PEP RECEPTOR 2(ZmPEPR2),was assigned as a PSR resistance gene.These results provide insights into the genetic architecture of resistance to PSR in maize,which should facilitate breeding maize for resistance to stalk rot.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
Grape white rot caused by Coniella vitis is a global concern in the grape industry.pH regulation is essential for cell growth,reproductive processes and pathogenicity in phytopathogenic fungi.In this study,we observed...Grape white rot caused by Coniella vitis is a global concern in the grape industry.pH regulation is essential for cell growth,reproductive processes and pathogenicity in phytopathogenic fungi.In this study,we observed that the growth rate,spore production and virulence of C.vitis significantly declined in alkaline pH,as well as the suppressive effect on secretion of hydrolytic enzymes.Transcriptomic and metabolomic analyses were used to investigate the responses of C.vitis to acidic(pH 5),neutral(pH 7)and alkaline environments(pH 9).We identified 728,1,780 and 3,386 differentially expressed genes(DEGs)at pH 5,pH 7 and pH 9,when compared with the host pH(pH 3),and 2,122 differently expressed metabolites(DEMs)in negative and positive ion mode.Most DEGs were involved in carbohydrate metabolic process,transmembrane transport,tricarboxylic acid cycle,peptide metabolic process,amide biosynthetic process,and organic acid metabolic process.In addition,metabolomic analysis revealed ABC transporters,indole alkaloid biosynthesis,diterpenoid biosynthesis,and carotenoid biosynthesis pathways in response to the pH change.Furthermore,we found that the aspartate synthesis metabolic route associated with the TCA cycle is a key limiting factor for the growth and development of C.vitis in alkaline environments,and aspartate supplementation enables C.vitis to grow in alkaline environments.Plant cell wall-degrading enzymes(PCWDEs)could contribute to the pathogenicity,when C.vitis infected at pH 3.Importantly,aflatrem biosynthesis in acidic environment might contribute to the virulence of C.vitis and has a risk of causing human health problems due to its acute neurotoxic effects.展开更多
Grape white rot is a fungal disease caused by Coniella diplodiella(Speg.)Sacc.that seriously affects fruit quality and yield;however,the underlying mechanism governing the plant response to C.diplodiella pathogens is ...Grape white rot is a fungal disease caused by Coniella diplodiella(Speg.)Sacc.that seriously affects fruit quality and yield;however,the underlying mechanism governing the plant response to C.diplodiella pathogens is still poorly understood.Here,we characterized a homeodomain(HD)transcription factor from grape(Vitis vinifera),VvOCP3,and demonstrated its signifcance in C.diplodiella resistance.Expression analysis showed that VvOCP3 expression was signifcantly down-regulated upon inoculation with C.diplodiella.Functional analysis with transient injection in grape berries and stable overexpression in grape calli demonstrated that VvOCP3 negatively regulates grape resistance to C.diplodiella.Further studies showed that VvOCP3 directly binds to the promoter of VvPR1(pathogenesis-related protein 1)and inhibits its expression,resulting in reduced resistance to C.diplodiella.In addition,VvOCP3 can interact with the type 2C protein phosphatase VvABI1,which is a negative modulator of the ABA signaling pathway.In summary,our findings suggest that VvOCP3 plays a crucial role in regulating white rot resistance in grape,and offer theoretical guidance for developing grape cultivars with enhanced C.diplodiella resistance by regulating the expression of VvOCP3.展开更多
Natural rubber is an indispensable material of strategic importance that has critical applications in industry and the military.However,the development of the natural rubber industry is impeded by the red root rot dis...Natural rubber is an indispensable material of strategic importance that has critical applications in industry and the military.However,the development of the natural rubber industry is impeded by the red root rot disease of rubber trees caused by Ganoderma pseudoferreum,which is one of the most devastating diseases in the rubber tree growing regions in China.To combat this disease,we screened the antifungal activity of 223 candidate bacterial strains against G.pseudoferreum,and found that Bacillus velezensis strain SF305 exhibited significant antifungal activity against G.pseudoferreum.Bacillus velezensis SF305 had a nearly 70%efficacy against the red root rot disease of rubber trees with the therapeutic treatment(Tre),while it exhibited over 90%protection effectiveness with the preventive treatment(Pre).The underlying biocontrol mechanism revealed that B.velezensis SF305 could reduce the disease severity of red root rot by degrading the mycelia of G.pseudoferreum.An antiSMASH analysis revealed that B.velezensis SF305 contains 15 gene clusters related to secondary metabolite synthesis,13 of which are conserved in species of B.velezensis,but surprisingly,B.velezensis SF305 possesses 2 unique secondary metabolite gene clusters.One is predicted to synthesize locillomycin,and the other is a novel nonribosomal peptides synthetase(NRPS)gene cluster.Genomic analysis showed that B.velezensis SF305 harbors genes involved in motility,chemotaxis,biofilm formation,stress resistance,volatile organic compounds(VOCs)and synthesis of the auxin indole-3-acetic acid(IAA),suggesting its plant growth-promoting rhizobacteria(PGPR)properties.Bacillus velezensis SF305 can promote plant growth and efficiently antagonize some important phytopathogenic fungi and bacteria.This study indicates that B.velezensis SF305 is a versatile plant probiotic bacterium.To the best of our knowledge,this is the first time a B.velezensis strain has been reported as a promising biocontrol agent against the red root rot disease of rubber trees.展开更多
To investigate the formation mechanism of stalk mechanical strength,clarify the mechanical mechanisms underlying stalk rot resistance,and establish core mechanical indicators for evaluating stalk strength,this study u...To investigate the formation mechanism of stalk mechanical strength,clarify the mechanical mechanisms underlying stalk rot resistance,and establish core mechanical indicators for evaluating stalk strength,this study utilized six maize varieties with different levels of stalk rot resistance including ZD619,HXD88,XZY801,XY696,LS1,and ZH431 as test materials.The density,moisture content,bending strength,rind puncture strength,and elastic modulus of maize stalks at different growth stages were determined,and their intrinsic relationships with stalk rot resistance were analyzed.Our results indicated that the stalk density,moisture content,bending strength,and rind puncture strength were responsive to stalk rot resistance.However,these indicators were in significant correlations with stalk rot resistance only after the physiological maturity of maize.In particular,stalk rind puncture strength exhibited the closest correlation with stalk rot resistance at the late stage of physiological maturity.Stalk density directly affected bending strength and rind puncture strength,and it indirectly affected the elastic modulus.The elastic modulus encompassing both load and displacement can improve the reliability of stalk strength evaluation,serving as the best indicator of stalk toughness.The attenuation amplitude of the elastic modulus was always the largest whether it was caused by the aggravation of the disease,the growth stage delay,or the internode position rise,which significantly improved the sensitivity of stalk strength evaluation.The elastic modulus of maize stalks was correlated with stalk rot resistance from the silking stage to late physiological maturity stage,which not only effectively improved the accuracy of stalk strength evaluation but also was beneficial to improving the efficiency of maize variety selection.In conclusion,the elastic modulus of maize stalks can be used to evaluate the maize stalk strength truly and accurately.Especially in the region with a high stalk rot incidence,it was beneficial to improving the breeding efficiency of the maize varieties suitable for mechanical harvesting.展开更多
Gibberella stalk rot(GSR)caused by Fusarium graminearum is one of the most devastating diseases of maize,seriously impacting maize yield and quality,as well as the ability to use technology of mechanical harvesting.En...Gibberella stalk rot(GSR)caused by Fusarium graminearum is one of the most devastating diseases of maize,seriously impacting maize yield and quality,as well as the ability to use technology of mechanical harvesting.Environmental conditions including photoperiod affect crop disease resistance.However,the mechanism underlying photoperiod-regulated maize GSR resistance remains unexplored.We found in this study that GSR resistance is regulated by the ZmPIF4.1(Phytochrome-Interacting Factor4)-ZmPTI1c(Pto-Interacting 1)-ZmMYB31 module coupled with photoperiod.The functional analysis of zmpti1c mutant indicated that ZmPTI1c negatively regulates maize GSR resistance.Short day promoted the disease progression in both zmpti1c and wild-type plants.ZmPTI1c promoter contains multiple predicted cis-acting elements for light responses.Yeast one-hybrid assay(Y1H),Electrophoretic mobility shift analysis(EMSA),and Dual-luciferase(LUC)reporter assays demonstrated that ZmPIF4.1 binds to the G-box in ZmPTI1c promoter and activates its expression.Moreover,expression levels of ZmPIF4 and ZmPTI1c were significantly higher under short day than under long day.ZmPTI1c interacted with and phosphorylated ZmMYB31.GSR resistance in zmmyb31 mutant was significantly increased than in wild type,indicating that ZmMYB31 also negatively regulated GSR resistance.Furthermore,ZmMYB31 suppressed the transcriptional activation of ZmPTI1c by ZmPIF4.1.Overall,ZmPIF4.1-ZmPTI1c-ZmMYB31negatively regulates maize immunity to GSR,which is likely modulated by photoperiod.展开更多
In 2022,an unknown bacterial disease was discovered in tobacco fields of Chenzhou,Hunan Province.In order to identify the pathogen of this disease,this study used tissue isolation method and streak plate method to iso...In 2022,an unknown bacterial disease was discovered in tobacco fields of Chenzhou,Hunan Province.In order to identify the pathogen of this disease,this study used tissue isolation method and streak plate method to isolate and purify the pathogen,conducted pathogenicity testing through in-vivo inoculation of Yunyan 87 tobacco plants,and identified the pathogen through morphological observation,physiological and biochemical characterization,and 16S rDNA and gyrB gene sequence analysis.The results indicated that 8 strains were obtained,named BY-1 to BY-8,by isolating the pathogen from infected plants.Pathogenicity test results showed that these isolated strains were the pathogen of the soft rot disease,consistent with Koch’s postulates.Combined with morphological observation and physiological and biochemical indicator determination,the strain was preliminarily identified as Pseudomonas.Homology comparison results revealed that the homology similarity of this strain to Pseudomonas flavescens was 99.86%.Phylogenetic analysis was conducted based on 16S rDNA and gyrB genes,and the results indicated that strain BY-8 was clustered with P.flavescens.Therefore,the pathogen was identified as P.flavescens,and the disease was named tobacco bacterial soft rot caused by P.flavescens.This was the first report of this disease on tobacco in China.展开更多
A compact and highly sensitive gas pressure and temperature sensor based on Fabry-Pérot interferometer(FPI)and fiber Bragg grating(FBG)is proposed and demonstrated experimentally in this paper.The theoretical mod...A compact and highly sensitive gas pressure and temperature sensor based on Fabry-Pérot interferometer(FPI)and fiber Bragg grating(FBG)is proposed and demonstrated experimentally in this paper.The theoretical model for pressure and temperature sensing is established.Building on this foundation,a novel micro silicon cavity sensor structure sensitive to pressure is devised downstream of an FBG.The concept of separate measurement and the mechanisms enhancing pressure sensitivity are meticulously analyzed,and the corresponding samples are fabricated.The experimental results indicate that the pressure sensitivity of the sensor is-747.849 nm/MPa in 0—100 k Pa and its linearity is 99.7%and it maintains good stability in 150 min.The sensor offers the advantages of compact size,robust construction,easy fabrication,and high sensitivity,making it potentially valuable for micro-pressure application.展开更多
Helianthus annuus L.as an oil seed crop is widely grown throughout the world.One of the most destructive diseases of sunflower is stem rot caused by Sclerotinia sclerotiorum.Oxalic acid is the major virulence factor o...Helianthus annuus L.as an oil seed crop is widely grown throughout the world.One of the most destructive diseases of sunflower is stem rot caused by Sclerotinia sclerotiorum.Oxalic acid is the major virulence factor of this necrotrophic pathogen.It is important to further investigate plant responses to this non-specific toxin.Therefore,in the present study,we compared the patterns of total soluble proteins and xylem morphology of partially resistant and susceptible sunflower lines after treatment with Sclerotinia culture filtrate.The basal stems of both lines were treated with 40 mM oxalic acid(pH 3.7)of fungus culture filtrate and samples were collected at 24,48 and 72 hours post treatment.In SDS-PAGE protein pattern new protein bands appeared in both lines after treatment.These observations suggest induction of stress-related proteins upon culture filtrate treatment.The identities of these new proteins need to be more clarify in future investigations.The changes in xylem morphology and degree of lignification of both lines was studied by light microscopy and microtome sectioning techniques after treatment with S.sclerotiorum culture filtrate.Anatomical investigations revealed changes in xylem diameter and xylem lignification of treated lines at various time points.More lignin deposition in xylem vessels of partially resistant line has been observed after treatment.In addition,the size of xylem vessels in partially resistant line has been sharply decreased upon pathogen filtrate treatment.The results of this study will help us gain a more complete understanding of resistance mechanisms to this cosmopolitan and devastating pathogen.展开更多
Hyperlipidemia has high morbidity. We explored the novel activities of six Chinese herbs before and after fermentation for preventing hyperlipidemia. The herbs were fermented with white rot fungi Ganoderma lucidum, a ...Hyperlipidemia has high morbidity. We explored the novel activities of six Chinese herbs before and after fermentation for preventing hyperlipidemia. The herbs were fermented with white rot fungi Ganoderma lucidum, a strain of EN2. Lovastatin was used as the positive control. Mice were treated with those herbs before and after fermentation treatment for 15 d and then injected peritoneally with Triton 3393. After the treatment, the serum total cholesterol （TC） and triglyceride （TG） were measured. More- over, the changes of the ingredients of those herbs were analyzed by fingerprint chromatography. The results showed that Herba leonuri before fermentation, Ramulus mori and Caulis lonicerae after fermentation, Radix sophoraeflavescentis before and after fermentation showed activities to prevent hypertriglyceridemia, while Ramulus mori and Herba leonuri before fermentation showed activities to prevent hypercholesterolemia. In addition, some new ingredients were appeared after fermentation. In conclusion, the novel activities of these herbs to prevent hyperlipidemia were identified and the new ingredients that emerged after fermentation warrant further exploration.展开更多
Protoplasts of Page tangelo (Citrus reticulata Blanco×C. paradisi Macf.) cell suspension culture were electrically fused with mesophyll protoplasts isolated from trifoliate orange (Poncirus trifoliata (L.) Raf.)....Protoplasts of Page tangelo (Citrus reticulata Blanco×C. paradisi Macf.) cell suspension culture were electrically fused with mesophyll protoplasts isolated from trifoliate orange (Poncirus trifoliata (L.) Raf.). More than 150 plantlets regenerated after 4-5 months of culture. The regenerated plants were trifoliate with well developed root systems. Root_tip chromosome counting of more than 20 randomly selected plants revealed that they were all tetraploids (2n=4x=36). RAPD analysis of 7 randomly selected plants verified their hybridity. Inoculation of citrus Phytophthora parasitica Dastar toxin on leaves of somatic hybrids and both parental genotypes showed that Page tangelo was moderately susceptible, and trifoliate orange was highly resistant while the somatic hybrids were resistant. The potential of this somatic hybrid as rootstock is also discussed.展开更多
[Objective] Antagonistic actinomyces of Amorphophallus konjac soft rot were isolated from the soil,the antibacterial activity of the fermentation was detected,and its active components were separated.[Method] The anta...[Objective] Antagonistic actinomyces of Amorphophallus konjac soft rot were isolated from the soil,the antibacterial activity of the fermentation was detected,and its active components were separated.[Method] The antagonistic actinomycetes were screened using plate confrontation culture method.The SJK18 antagonistic strain with strong activity was conducted single-factor tests using different carbon sources,nitrogen sources,temperatures and pH value as the culture condition,and the antibacterial activities of fermentation liquid was determined,respectively.The fermentation liquid of antagonistic strain was extracted with alcohol and acetic ester,and their antibacterial activities were determined.[Result] A total of 112 strains of actinomycetes were obtained,and 11 strains had antibacterial activity.The antibacterial activity of SJK18 strain was the strongest in the single-factor test,when the corn powder was adopted as the carbon sources,KNO3 was the nitrogen source,the temperature was 30 ℃ and the pH was 6.0,the appropriate pH value for the activity was 5.5-10.0.The diameters of inhibition zone of alcohol extract and raffinate of ethyl acetate were 17.0 and 20.0 mm,respectively,while the extraction of ethyl acetate had no antibacterial activity.[Conclusion] A strain of actinomyces with strong antibacterial activity against soft rot of A.konjac was obtained.展开更多
基金The Major Science and Technology Project of Henan Province(Grant No.201300111000)The Basic scientific Research Project of Henan Academy of Agricultural Sciences(Grant No.2022ZC37,2023ZC46)。
文摘Peanut(Arachis hypogaea),which is widely cultivated across the world,provides high-quality vegetable oil,protein,dietary fiber,minerals,and vitamins for humans.However,in field conditions,the peanut is easily affected by various biotic and abiotic stresses.Diplodia gossypina is the dominant pathogen causing severe collar rot on peanuts.To dissect the pathogenic mechanism of D.gossypina,genome sequencing analysis was performed by using the D.gossypina strain A20_4.The sequencing data showed that the genome assembly size of D.gossypina A20_4 is 43.03 Mb with a GC content of 54.91%.The de novo assembly identified a total of 10,745 genes,containing 41,526 coding sequences and 2.20%of repeat sequences,of which 6,461 genes(60.13%)were annotated using BlastP from GO annotation,3,245 genes(30.20%)and 3,093 genes(28.79%)were annotated from KOG and KEGG annotations,respectively.Meanwhile,the secreted proteins and effectors in 10,745 protein sequences encoded by the whole genome of D.gossypina A20_4 were analyzed,and the results showed that there are 790 secreted protein genes including 220 carbohydrate-active enzymes and 224 potential effector proteins.The functions of 222 potential effector proteins can be annotated by PHI-base.According to the annotation results,12 key pathogenic factors were identified in D.gossypina A20_4.Moreover,a serine/threonine protein kinase SNF1 gene required for autophagy process was identified and analyzed.Deciphering the whole genome of D.gossypina A20_4 provides us with novel insights into understanding evolution,pathogenic molecular mechanism,host-pathogen interaction,and many other complexities of the pathogen.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFD1200101)the Earmarked Fund for Modern Agro-industry Technology Research System(Grant No.CARS-23)Science and Technology Innovation Program of the Chinese Academy of Agricultural Science(Grant No.CAAS-ASTIP-IVFCAAS).
文摘Bacterial soft rot(BSR)caused by Pectobacterium carotovorum subsp.brasiliense(Pcb)is a serious bacterial disease which negatively impact yield and quality in cucumber.However,the genetic mechanism of BSR resistance in cucumber has not been reported.Here,we investigated the BSR resistance of 119 cucumber core germplasm worldwide at the seedling stage and identified 26 accessions highly resistant to BSR.A total of 1642740 single-nucleotide polymorphisms(SNPs)were used to conduct GWAS,and five loci associated with BSR resistance were detected on four chromosomes:gBSR2.1,gBSR2.2,gBSR3.1,gBSR4.1 and gBSR5.1.Based on haplotype analysis,sequence polymorphisms,functional annotation and qRT-PCR analysis,six candidate genes were identified within the five loci.CsaV3_2G014450,CsaV3_2G014490,CsaV3_2G016000,CsaV3_3G000850,CsaV3_4G033150,and CsaV3_5G000390 each had nonsynonymous SNPs,and were significantly up-regulated in the resistant genotypes after inoculation.And CsaV3_5G000390 in the susceptible genotype was significantly up-regulated after inoculation.The identification of these candidate genes lays a foundation for understanding the genetic mechanism of BSR resistance in cucumber.Generally,our study mined genes associated with BSR resistance in cucumber seedlings and will assist the breeding of BSR-resistant cucumber cultivars.
基金supported by National Natural Science Foundation of China(32302371 to Junbin Chen)the National Key Research and Development Program,Ministry of Science and Technology of China(2022YFD1201802 to Wangsheng Zhu)Research Program from State Key Laboratory of Maize Biobreeding(SKLMB2424 to Wangsheng Zhu).
文摘Pythium stalk rot(PSR)is a destructive disease of maize,severely affecting yield and grain quality.The identification of quantitative trait loci(QTL)or genes for resistance to PSR forms the basis of diseaseresistant hybrids breeding.In this study,a major QTL,Resistance to Pythium stalk rot 1(RPSR1),was identified from a set of recombinant inbred lines derived from MS71 and POP.Using a recombinant progeny testing strategy,RPSR1 was fine-mapped in a 472 kb interval.Through candidate gene expression,gene knock-down and knock-out studies,a leucine-rich repeat receptor-like kinase gene,PEP RECEPTOR 2(ZmPEPR2),was assigned as a PSR resistance gene.These results provide insights into the genetic architecture of resistance to PSR in maize,which should facilitate breeding maize for resistance to stalk rot.
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 Shandong Provincial Natural Science Foundation,China(ZR2021QC131)the Shandong Province Key Research and Development Plan,China(2022TZXD001102)+1 种基金the Shandong Province Demonstration Project for Model Construction in Rural Revitalization Service,China(2022DXAL0226)the Innovation Project of Shandong Academy of Agricultural Sciences,China(CXGC2023F15,CXGC2023A41,and CXGC2023A47)。
文摘Grape white rot caused by Coniella vitis is a global concern in the grape industry.pH regulation is essential for cell growth,reproductive processes and pathogenicity in phytopathogenic fungi.In this study,we observed that the growth rate,spore production and virulence of C.vitis significantly declined in alkaline pH,as well as the suppressive effect on secretion of hydrolytic enzymes.Transcriptomic and metabolomic analyses were used to investigate the responses of C.vitis to acidic(pH 5),neutral(pH 7)and alkaline environments(pH 9).We identified 728,1,780 and 3,386 differentially expressed genes(DEGs)at pH 5,pH 7 and pH 9,when compared with the host pH(pH 3),and 2,122 differently expressed metabolites(DEMs)in negative and positive ion mode.Most DEGs were involved in carbohydrate metabolic process,transmembrane transport,tricarboxylic acid cycle,peptide metabolic process,amide biosynthetic process,and organic acid metabolic process.In addition,metabolomic analysis revealed ABC transporters,indole alkaloid biosynthesis,diterpenoid biosynthesis,and carotenoid biosynthesis pathways in response to the pH change.Furthermore,we found that the aspartate synthesis metabolic route associated with the TCA cycle is a key limiting factor for the growth and development of C.vitis in alkaline environments,and aspartate supplementation enables C.vitis to grow in alkaline environments.Plant cell wall-degrading enzymes(PCWDEs)could contribute to the pathogenicity,when C.vitis infected at pH 3.Importantly,aflatrem biosynthesis in acidic environment might contribute to the virulence of C.vitis and has a risk of causing human health problems due to its acute neurotoxic effects.
基金funded by the National Natural Science Foundation of China(31972368)the China Agriculture Research System(CARS-29-yc-6)+1 种基金the Major Agricultural Science Projects of Liaoning Province,China(2023JH1/10200004)the Science and Technology Program of Shenyang,China(23-410-2-03)。
文摘Grape white rot is a fungal disease caused by Coniella diplodiella(Speg.)Sacc.that seriously affects fruit quality and yield;however,the underlying mechanism governing the plant response to C.diplodiella pathogens is still poorly understood.Here,we characterized a homeodomain(HD)transcription factor from grape(Vitis vinifera),VvOCP3,and demonstrated its signifcance in C.diplodiella resistance.Expression analysis showed that VvOCP3 expression was signifcantly down-regulated upon inoculation with C.diplodiella.Functional analysis with transient injection in grape berries and stable overexpression in grape calli demonstrated that VvOCP3 negatively regulates grape resistance to C.diplodiella.Further studies showed that VvOCP3 directly binds to the promoter of VvPR1(pathogenesis-related protein 1)and inhibits its expression,resulting in reduced resistance to C.diplodiella.In addition,VvOCP3 can interact with the type 2C protein phosphatase VvABI1,which is a negative modulator of the ABA signaling pathway.In summary,our findings suggest that VvOCP3 plays a crucial role in regulating white rot resistance in grape,and offer theoretical guidance for developing grape cultivars with enhanced C.diplodiella resistance by regulating the expression of VvOCP3.
基金financially supported by the National Key Research and Development Program of China(2023YFD1200204)the Special Fund for Hainan Excellent Team“Rubber Genetics and Breeding”,China(20210203)。
文摘Natural rubber is an indispensable material of strategic importance that has critical applications in industry and the military.However,the development of the natural rubber industry is impeded by the red root rot disease of rubber trees caused by Ganoderma pseudoferreum,which is one of the most devastating diseases in the rubber tree growing regions in China.To combat this disease,we screened the antifungal activity of 223 candidate bacterial strains against G.pseudoferreum,and found that Bacillus velezensis strain SF305 exhibited significant antifungal activity against G.pseudoferreum.Bacillus velezensis SF305 had a nearly 70%efficacy against the red root rot disease of rubber trees with the therapeutic treatment(Tre),while it exhibited over 90%protection effectiveness with the preventive treatment(Pre).The underlying biocontrol mechanism revealed that B.velezensis SF305 could reduce the disease severity of red root rot by degrading the mycelia of G.pseudoferreum.An antiSMASH analysis revealed that B.velezensis SF305 contains 15 gene clusters related to secondary metabolite synthesis,13 of which are conserved in species of B.velezensis,but surprisingly,B.velezensis SF305 possesses 2 unique secondary metabolite gene clusters.One is predicted to synthesize locillomycin,and the other is a novel nonribosomal peptides synthetase(NRPS)gene cluster.Genomic analysis showed that B.velezensis SF305 harbors genes involved in motility,chemotaxis,biofilm formation,stress resistance,volatile organic compounds(VOCs)and synthesis of the auxin indole-3-acetic acid(IAA),suggesting its plant growth-promoting rhizobacteria(PGPR)properties.Bacillus velezensis SF305 can promote plant growth and efficiently antagonize some important phytopathogenic fungi and bacteria.This study indicates that B.velezensis SF305 is a versatile plant probiotic bacterium.To the best of our knowledge,this is the first time a B.velezensis strain has been reported as a promising biocontrol agent against the red root rot disease of rubber trees.
文摘To investigate the formation mechanism of stalk mechanical strength,clarify the mechanical mechanisms underlying stalk rot resistance,and establish core mechanical indicators for evaluating stalk strength,this study utilized six maize varieties with different levels of stalk rot resistance including ZD619,HXD88,XZY801,XY696,LS1,and ZH431 as test materials.The density,moisture content,bending strength,rind puncture strength,and elastic modulus of maize stalks at different growth stages were determined,and their intrinsic relationships with stalk rot resistance were analyzed.Our results indicated that the stalk density,moisture content,bending strength,and rind puncture strength were responsive to stalk rot resistance.However,these indicators were in significant correlations with stalk rot resistance only after the physiological maturity of maize.In particular,stalk rind puncture strength exhibited the closest correlation with stalk rot resistance at the late stage of physiological maturity.Stalk density directly affected bending strength and rind puncture strength,and it indirectly affected the elastic modulus.The elastic modulus encompassing both load and displacement can improve the reliability of stalk strength evaluation,serving as the best indicator of stalk toughness.The attenuation amplitude of the elastic modulus was always the largest whether it was caused by the aggravation of the disease,the growth stage delay,or the internode position rise,which significantly improved the sensitivity of stalk strength evaluation.The elastic modulus of maize stalks was correlated with stalk rot resistance from the silking stage to late physiological maturity stage,which not only effectively improved the accuracy of stalk strength evaluation but also was beneficial to improving the efficiency of maize variety selection.In conclusion,the elastic modulus of maize stalks can be used to evaluate the maize stalk strength truly and accurately.Especially in the region with a high stalk rot incidence,it was beneficial to improving the breeding efficiency of the maize varieties suitable for mechanical harvesting.
基金supported financially by the grants from the JBGS[2021]002 project from the Jiangsu Governmentthe National Nature Science Foundation of China(32472095)+2 种基金the National Key Research and Development Program of China(2020YFE02029002)Collaborative Innovation Center for Modern Crop Production(CIC-MCP)to Xiquan Gaosupported in part by the high-performance computing platform of Bioinformatics Center,Nanjing Agricultural University。
文摘Gibberella stalk rot(GSR)caused by Fusarium graminearum is one of the most devastating diseases of maize,seriously impacting maize yield and quality,as well as the ability to use technology of mechanical harvesting.Environmental conditions including photoperiod affect crop disease resistance.However,the mechanism underlying photoperiod-regulated maize GSR resistance remains unexplored.We found in this study that GSR resistance is regulated by the ZmPIF4.1(Phytochrome-Interacting Factor4)-ZmPTI1c(Pto-Interacting 1)-ZmMYB31 module coupled with photoperiod.The functional analysis of zmpti1c mutant indicated that ZmPTI1c negatively regulates maize GSR resistance.Short day promoted the disease progression in both zmpti1c and wild-type plants.ZmPTI1c promoter contains multiple predicted cis-acting elements for light responses.Yeast one-hybrid assay(Y1H),Electrophoretic mobility shift analysis(EMSA),and Dual-luciferase(LUC)reporter assays demonstrated that ZmPIF4.1 binds to the G-box in ZmPTI1c promoter and activates its expression.Moreover,expression levels of ZmPIF4 and ZmPTI1c were significantly higher under short day than under long day.ZmPTI1c interacted with and phosphorylated ZmMYB31.GSR resistance in zmmyb31 mutant was significantly increased than in wild type,indicating that ZmMYB31 also negatively regulated GSR resistance.Furthermore,ZmMYB31 suppressed the transcriptional activation of ZmPTI1c by ZmPIF4.1.Overall,ZmPIF4.1-ZmPTI1c-ZmMYB31negatively regulates maize immunity to GSR,which is likely modulated by photoperiod.
文摘In 2022,an unknown bacterial disease was discovered in tobacco fields of Chenzhou,Hunan Province.In order to identify the pathogen of this disease,this study used tissue isolation method and streak plate method to isolate and purify the pathogen,conducted pathogenicity testing through in-vivo inoculation of Yunyan 87 tobacco plants,and identified the pathogen through morphological observation,physiological and biochemical characterization,and 16S rDNA and gyrB gene sequence analysis.The results indicated that 8 strains were obtained,named BY-1 to BY-8,by isolating the pathogen from infected plants.Pathogenicity test results showed that these isolated strains were the pathogen of the soft rot disease,consistent with Koch’s postulates.Combined with morphological observation and physiological and biochemical indicator determination,the strain was preliminarily identified as Pseudomonas.Homology comparison results revealed that the homology similarity of this strain to Pseudomonas flavescens was 99.86%.Phylogenetic analysis was conducted based on 16S rDNA and gyrB genes,and the results indicated that strain BY-8 was clustered with P.flavescens.Therefore,the pathogen was identified as P.flavescens,and the disease was named tobacco bacterial soft rot caused by P.flavescens.This was the first report of this disease on tobacco in China.
基金supported in part by the National Natural Science Foundation of China(Nos.61735014 and 61927812)the Shaanxi Provincial Education Department(No.18JS093)+2 种基金the Natural Science Basic Research Program of Shaanxi Province(No.2024JC-YBMS-530)the Operation Fund of Logging Key Laboratory of Group Company(No.2021DQ0107-11)the Graduate Student Innovation Fund of Xi’an Shiyou University(No.YCS23213193)。
文摘A compact and highly sensitive gas pressure and temperature sensor based on Fabry-Pérot interferometer(FPI)and fiber Bragg grating(FBG)is proposed and demonstrated experimentally in this paper.The theoretical model for pressure and temperature sensing is established.Building on this foundation,a novel micro silicon cavity sensor structure sensitive to pressure is devised downstream of an FBG.The concept of separate measurement and the mechanisms enhancing pressure sensitivity are meticulously analyzed,and the corresponding samples are fabricated.The experimental results indicate that the pressure sensitivity of the sensor is-747.849 nm/MPa in 0—100 k Pa and its linearity is 99.7%and it maintains good stability in 150 min.The sensor offers the advantages of compact size,robust construction,easy fabrication,and high sensitivity,making it potentially valuable for micro-pressure application.
文摘Helianthus annuus L.as an oil seed crop is widely grown throughout the world.One of the most destructive diseases of sunflower is stem rot caused by Sclerotinia sclerotiorum.Oxalic acid is the major virulence factor of this necrotrophic pathogen.It is important to further investigate plant responses to this non-specific toxin.Therefore,in the present study,we compared the patterns of total soluble proteins and xylem morphology of partially resistant and susceptible sunflower lines after treatment with Sclerotinia culture filtrate.The basal stems of both lines were treated with 40 mM oxalic acid(pH 3.7)of fungus culture filtrate and samples were collected at 24,48 and 72 hours post treatment.In SDS-PAGE protein pattern new protein bands appeared in both lines after treatment.These observations suggest induction of stress-related proteins upon culture filtrate treatment.The identities of these new proteins need to be more clarify in future investigations.The changes in xylem morphology and degree of lignification of both lines was studied by light microscopy and microtome sectioning techniques after treatment with S.sclerotiorum culture filtrate.Anatomical investigations revealed changes in xylem diameter and xylem lignification of treated lines at various time points.More lignin deposition in xylem vessels of partially resistant line has been observed after treatment.In addition,the size of xylem vessels in partially resistant line has been sharply decreased upon pathogen filtrate treatment.The results of this study will help us gain a more complete understanding of resistance mechanisms to this cosmopolitan and devastating pathogen.
文摘Hyperlipidemia has high morbidity. We explored the novel activities of six Chinese herbs before and after fermentation for preventing hyperlipidemia. The herbs were fermented with white rot fungi Ganoderma lucidum, a strain of EN2. Lovastatin was used as the positive control. Mice were treated with those herbs before and after fermentation treatment for 15 d and then injected peritoneally with Triton 3393. After the treatment, the serum total cholesterol （TC） and triglyceride （TG） were measured. More- over, the changes of the ingredients of those herbs were analyzed by fingerprint chromatography. The results showed that Herba leonuri before fermentation, Ramulus mori and Caulis lonicerae after fermentation, Radix sophoraeflavescentis before and after fermentation showed activities to prevent hypertriglyceridemia, while Ramulus mori and Herba leonuri before fermentation showed activities to prevent hypercholesterolemia. In addition, some new ingredients were appeared after fermentation. In conclusion, the novel activities of these herbs to prevent hyperlipidemia were identified and the new ingredients that emerged after fermentation warrant further exploration.
文摘Protoplasts of Page tangelo (Citrus reticulata Blanco×C. paradisi Macf.) cell suspension culture were electrically fused with mesophyll protoplasts isolated from trifoliate orange (Poncirus trifoliata (L.) Raf.). More than 150 plantlets regenerated after 4-5 months of culture. The regenerated plants were trifoliate with well developed root systems. Root_tip chromosome counting of more than 20 randomly selected plants revealed that they were all tetraploids (2n=4x=36). RAPD analysis of 7 randomly selected plants verified their hybridity. Inoculation of citrus Phytophthora parasitica Dastar toxin on leaves of somatic hybrids and both parental genotypes showed that Page tangelo was moderately susceptible, and trifoliate orange was highly resistant while the somatic hybrids were resistant. The potential of this somatic hybrid as rootstock is also discussed.
基金Supported by Key Laboratory Fund in Hubei Province(2008NP11)Science and Technology Research and Development Project in Yichang City(A09302-17)~~
文摘[Objective] Antagonistic actinomyces of Amorphophallus konjac soft rot were isolated from the soil,the antibacterial activity of the fermentation was detected,and its active components were separated.[Method] The antagonistic actinomycetes were screened using plate confrontation culture method.The SJK18 antagonistic strain with strong activity was conducted single-factor tests using different carbon sources,nitrogen sources,temperatures and pH value as the culture condition,and the antibacterial activities of fermentation liquid was determined,respectively.The fermentation liquid of antagonistic strain was extracted with alcohol and acetic ester,and their antibacterial activities were determined.[Result] A total of 112 strains of actinomycetes were obtained,and 11 strains had antibacterial activity.The antibacterial activity of SJK18 strain was the strongest in the single-factor test,when the corn powder was adopted as the carbon sources,KNO3 was the nitrogen source,the temperature was 30 ℃ and the pH was 6.0,the appropriate pH value for the activity was 5.5-10.0.The diameters of inhibition zone of alcohol extract and raffinate of ethyl acetate were 17.0 and 20.0 mm,respectively,while the extraction of ethyl acetate had no antibacterial activity.[Conclusion] A strain of actinomyces with strong antibacterial activity against soft rot of A.konjac was obtained.
