Based on multi-alignment of complete polyprotein amino acid sequences of genus Potyvirus,five degenerated primers were designedThey were Sprimer(5′-GGX AAY AAY AGY GGX CAZ CC-3′),pNIa(+)(5′-TNY TGG AAM CAY TGG A...Based on multi-alignment of complete polyprotein amino acid sequences of genus Potyvirus,five degenerated primers were designedThey were Sprimer(5′-GGX AAY AAY AGY GGX CAZ CC-3′),pNIa(+)(5′-TNY TGG AAM CAY TGG AT-3′),pCI2(+)(5′-GCX ACX AAX ATX ATX GAX AA-3′),pCI1(+)(5′-GTX GGX TCX GGX AAX TCX AC-3′)and pHC(+)(5′-TGY GAY AAY CAZ TTX GA-3′)(X=A,T,C or G:Y=T or C;Z=A or G;N=A or T;M=A,T or G)Using degenerated PCR and modified RACE methods,a protocol for determination of complete genome sequence of potyviruses was established and proved to be successful on five展开更多
Soybean mosaic virus （SMV）, a member of the genus Potyvirus, is a major pathogen of soybean plants in China, and 16 SMV strains have been identified nationwide based on a former detailed SMV classification system. A...Soybean mosaic virus （SMV）, a member of the genus Potyvirus, is a major pathogen of soybean plants in China, and 16 SMV strains have been identified nationwide based on a former detailed SMV classification system. As the P3 gene is thought to be involved in viral replication, systemic infection, pathogenicity, and overcoming resistance, knowledge of the P3 gene sequences of SMV and other potyviruses would be useful in efforts to know the genetic relationships among them and control the disease. P3 gene sequences were obtained from representative isolates of the above-mentioned 16 SMV strains and were compared with other SMV strains and 16 Potyvirus species from the National Center for Biotechnology GenBank database. The P3 genes from the 16 SMV isolates are composed of 1041 nucleotides, encoding 347 amino acids, and share 90.7-100% nucleotide （NT） sequence identities and 95.1-100% amino acid （AA） sequence identities. The P3 coding regions of the 16 SMV isolates share high identities （92.4-98.9% NT and 96.0-100% AA） with the reported Korean isolates, followed by the USA isolates （88.5-97.9% NT and 91.4-98.6% AA）, and share low identities （80.5-85.2% NT and 82.1-84.7% AA） with the reported HZ 1 and P isolates from Pinellia ternata. The sequence identities of the P3 genes between SMV and the 16 potyviruses varied from 44.4 to 81.9% in the NT sequences and from 21.4 to 85.3% in the AA sequences, respectively. Among them, SMV was closely related to Watermelon mosaic virus （WMV）, with 76.0-81.9% NT and 77.5-85.3% AA identities. In addition, the SMV isolates and potyvirus species were clustered into six distinct groups. All the SMV strains isolated from soybean were clustered in Group I, and the remaining species were clustered in other groups. A multiple sequence alignment analysis of the C-terminal regions indicated that the P3 genes within a species were highly conserved, whereas those among species were relatively variable.展开更多
A headspace solid-phase microextraction-gas chromatography-mass spectrometry(HS-SPME/GC-MS)method was used to study the volatile organic compounds(VOCs)associated with the differential immune response of tomato plants...A headspace solid-phase microextraction-gas chromatography-mass spectrometry(HS-SPME/GC-MS)method was used to study the volatile organic compounds(VOCs)associated with the differential immune response of tomato plants infected with the recombinant strain of potato virus Y(PVY^(C)-to),necrogenic to tomato.Analysis was carried out in UC82(UC),a virus susceptible tomato variety,comparing the same UC plants grafted or not onto a virus tolerant tomato ecotype,Manduria(Ma);the three types of samples used for the GC-MS analysis were mock-inoculated UC/Ma plants,UC/Ma+PVY^(C)-to and UC+PVY^(C)-to plants;the VOCs obtained were 111.Results from symptomatic PVY^(C)-to-infected UC plants showed a VOCs composition enriched in alcohols,fatty acid derivates,benzenoids,and salicylic acid derivatives,while in mock-inoculated UC/Ma plants VOCs were mainly characterized by methyl ester compounds.The VOC profile was in line with RNAseq data analyses,denoting that PVY^(C)-to viral RNA accumulation and disease symptoms induce the specific transcriptional activation of genes involved in VOCs biosynthesis.Furthermore,principal component analysis highlighted that VOCs of PVY^(C)-to-infected and mock-inoculated grafted plants were much closer each other than that of symptomatic PVY^(C)-to-infected non-grafted UC plants.These results suggest that VOCs profiles of tomato plants are related to the viral RNA accumulation,disease intensity and graft-derived tolerance to PVY^(C)-to infection.展开更多
To fight against invasion by pathogens,plants have evolved an elaborate innate immune system,of which the nucleotide-binding domain leucine-rich repeat-containing receptor(NLR)acts as the sensor and immune executor.Po...To fight against invasion by pathogens,plants have evolved an elaborate innate immune system,of which the nucleotide-binding domain leucine-rich repeat-containing receptor(NLR)acts as the sensor and immune executor.Potyviruses,comprising one of the largest genera of plant viruses,cause severe crop yield losses worldwide.Inherited crop resistance to potyviruses can be used in breeding and plant transgenesis to control disease development.This review summarizes achievements in mapping and cloning NLR genes conferring dominant resistance against potyvirus in the families Fabaceae,Solanaceae,Brassicaceae,and Cucurbitaceae.It compares mechanisms of potyviral protein recognition and downstream signaling employed by NLRs and discusses strategies for exploiting NLRs to better control diseases caused by potyviruses.展开更多
Potyviruses are major constraints to grain legume production by causing significant yield losses. Potyviruses infecting Bambara groundnut (Vigna subterranea) were investigated in Burkina Faso. Leaf samples collected f...Potyviruses are major constraints to grain legume production by causing significant yield losses. Potyviruses infecting Bambara groundnut (Vigna subterranea) were investigated in Burkina Faso. Leaf samples collected from three agroclimatic zones were subjected to RT-PCR and sequence analyses. Of a total of 135 samples, 36 (26.67%) were detected positive in RT-PCR tests using potyvirus universal primers. Analysis of full coat protein (cp) sequences from 24 isolates revealed the occurrence of three groups of Bambara groundnut-infecting potyviruses. Virus isolates in group 1 shared 94.5% - 100% nucleotide (nt) identity with CABMV whereas those in group 2 and group 3 were distantly related Bean common necrosis virus (BCMNV) and Passiflora virus Ugandan which were their respective closest potyviruses. Group 2 shared 77.1% nt and 78.8% - 79.9% aa identity with BCMNV and group 3 shared 77.3% - 78.3% nt and 80.7% - 81.5% aa identity with Passiflora virus Ugandan. All three groups were confirmed by phylogenetic analyses. Taking into account potyvirus demarcation criteria, group 1 isolates belonged to CABMV species. Group 2 and group 3 were assigned to a potentially new potyviruses species and designated Bambara groundnut potyvirus 1 (BGPV1) and Bambara groundnut potyvirus 2 (BGPV2).展开更多
Recessive resistance mediated by mutations in the eukaryotic translation initiation factor 4E(eIF4E),has proven effective against diverse potyviruses and is extensively utilized in breeding programs.However,the rise o...Recessive resistance mediated by mutations in the eukaryotic translation initiation factor 4E(eIF4E),has proven effective against diverse potyviruses and is extensively utilized in breeding programs.However,the rise of resistance-breaking(RB)strains and emerging potyviral species necessitates the development of more durable and broad-spectrum resistance strategies.In this study,our field survey in Yunnan,China,identified potato virus Y(PVY)RB isolates,as well as the prevalence of tobacco vein banding mosaic virus(TVBMV)and chilli veinal mottle virus(ChiVMV),in tobacco carrying the recessive va locus,which lacks the eIF4E1-S susceptibility gene,due to a chromosomal deletion.Protein interaction and viral infection assays demonstrated that both eIF4E1-S and eIFiso4E-T are used by PVY RB as susceptibility factors for infection,with the combined inactivation of these genes confering durable resistance.Similarly,the knockout of eIFiso4E-S,in the va genetic background,provided effective resistance to TVBMV and reduced susceptibility to ChiVMV.Notably,pyramiding mutations in eIFiso4E-S and eIFiso4E-T,in va tobacco,generated plants exhibiting robust,broad-spectrum resistance,to all three viruses,without compromising plant development.These findings underscore the potential of stacking eIF4E mutations to engineer durable,broad-spectrum resistance to potyviruses in tobacco,offering a promising strategy for crop improvement.展开更多
Pennisetum plants(Pennisetum alopecuroides L.),displaying a dwarfing phenotype along with delayed flowering and mosaic symptom on leaves,were found in Beijing,China.Flexuous filamentous particles with a size of approx...Pennisetum plants(Pennisetum alopecuroides L.),displaying a dwarfing phenotype along with delayed flowering and mosaic symptom on leaves,were found in Beijing,China.Flexuous filamentous particles with a size of approximate 15×850 nm were observed in symptomatic leaves via transmission electron microscopy.Deep sequencing of small RNAs(sRNA)from symptomatic leaves and analysis of sRNA populations were then conducted to determine the genome sequence of the viral agent in diseased plant tissues.It showed that the viral agent had one positive-sense and single-stranded RNA genome,which consisted of 9717 nucleotides(nts)excluding poly(A)tail.The complete viral genome contained a large open reading frame,encoding a polyprotein of 3131 amino acids(aa).Sequence comparison and phylogenetic analysis demonstrated that the viral agent belonged to the genus Potyvirus in the family Potyviridae.In the cladogram it was most closely related to johnsongrass mosaic virus,sharing 72%nt and 65%aa sequence identity.This viral agent was provisionally named pennisetum alopecuroides mosaic virus(PalMV).Subsequently,it was confirmed that PalMV is the causal agent of this new disease in P.alopecuroides by Koch’s postulates and reverse transcription-polymerase chain reaction analysis.Moreover,maize,millet,wheat,sorghum and rice plants were experimentally infected by PalMV via rub inoculation.Consequently,we proposed that PalMV could be a potentially dangerous virus threating a wide range of cereal crops.展开更多
Coat protein(CP)is required for potyviruses to move and establish a systemic infection in plants.π-stackings formed by aromatic residues play critical roles in maintaining protein stability and functions.As we know,m...Coat protein(CP)is required for potyviruses to move and establish a systemic infection in plants.π-stackings formed by aromatic residues play critical roles in maintaining protein stability and functions.As we know,many aromatic residues located in the core region of potyvirus CPs are conserved.However,their roles in potyvirus infection remain largely unknown.Here,through analysis of the three-dimensional model of the tobacco vein banding mosaic virus(TVBMV;genus Potyvirus)CP,16 aromatic residues were predicated to formπ-stackings.The results of transient expression experiments demonstrated that deletion of any of these 16 aromatic residues reduced CP accumulation.Infectivity assays showed that deletion of any of these aromatic residues in the TVBMV infectious clone abolished cell-to-cell movement and reduced replication of the virus.Substitution of Y^(105) and Y^(147) individually with non-aromatic residues alanine or glycine reduced CP accumulation,virus replication,and abolished the ability of TVBMV to move intercellularly,while substitution of these two residues individually with aromatic residues phenylalanine or tryptophan,had no or little effect on CP accumulation and TVBMV systemic movement and replication.Similar results were obtained from the CP mutants of watermelon mosaic virus(WMV,genus Potyvirus).Taken together,our results demonstrate that multiple aromatic residues in CP are involved in potyvirus movement by formingπ-stackings to maintain CP accumulation.展开更多
Viral diseases are among the most critical damaging factors that impose a global threat to the cucurbit industry.China is the world’s leading country for the production and consumption of cucurbits.Guangdong,a provin...Viral diseases are among the most critical damaging factors that impose a global threat to the cucurbit industry.China is the world’s leading country for the production and consumption of cucurbits.Guangdong,a province in southern China dominated by the tropical and subtropical climate,favors the survival of different plant viruses and their vectors.Five main cucurbit crops showing various disease symptoms were surveyed and collected to identify viruses infecting cucurbits in Guangdong during 2018–2020.In the field,the incidence ranged from 5-30%,or even 60-100% in the case of severely infected cucurbits.A total of 357 symptomatic samples were collected and subsequently screened for cucurbit viruses by small RNA deep sequencing and assembly(sRSA).Seventeen virus species belonging to 10 genera were identified in the five main cucurbit crops.The most common viruses were papaya ringspot virus(PRSV;Potyvirus),zucchini tigre mosaic virus(ZTMV;Potyvirus),zucchini yellow mosaic virus(ZYMV;Potyvirus),and watermelon silver mottle virus(WSMoV;Orthotospovirus),with infection rates of 24.4,19.0,17.1,and 14.3%,respectively.Notably,the most prevalent viruses were melon yellow spot orthotospovirus(MYSV)in cucumber,PRSV in squash,cucumber green mottle mosaic virus(CGMMV;Tobamovirus)in bottle gourd,WSMoV in white gourd,and ZYMV in luffa.Mixed infections were prevalent,and the types of mixed infections varied substantially in different cucurbit crops.Moreover,the full-length nucleotide sequences of watermelon green mottle mosaic virus(WGMMV),CGMMV,and watermelon virus A(WVA;Wamavirus)identified in bottle gourd were cloned and analyzed.This study is the first reporting WGMMV infecting bottle gourd in China mainland.In summary,the results demonstrate that in Guangdong,the most prevalent viruses belong to potyviruses,orthotospoviruses,and tobamoviruses groups.The findings will facilitate agricultural researchers and farmers to plan and implement effective disease control strategies aiming at timely detection and management of cucurbit-infecting viral pathogens.展开更多
文摘Based on multi-alignment of complete polyprotein amino acid sequences of genus Potyvirus,five degenerated primers were designedThey were Sprimer(5′-GGX AAY AAY AGY GGX CAZ CC-3′),pNIa(+)(5′-TNY TGG AAM CAY TGG AT-3′),pCI2(+)(5′-GCX ACX AAX ATX ATX GAX AA-3′),pCI1(+)(5′-GTX GGX TCX GGX AAX TCX AC-3′)and pHC(+)(5′-TGY GAY AAY CAZ TTX GA-3′)(X=A,T,C or G:Y=T or C;Z=A or G;N=A or T;M=A,T or G)Using degenerated PCR and modified RACE methods,a protocol for determination of complete genome sequence of potyviruses was established and proved to be successful on five
基金supported by the National Natural Science Foundation of China(30671266,31101164)the National Basic Research Program of China(2006CB101708,2009CB118404)+2 种基金the National 863 Program of China(2006AA100104)the 111 Project from Ministry of Education of China(B08025)the Youth Science and Technology Innovation Foundation of Nanjing Agriculture University,China(KJ2010002)
文摘Soybean mosaic virus （SMV）, a member of the genus Potyvirus, is a major pathogen of soybean plants in China, and 16 SMV strains have been identified nationwide based on a former detailed SMV classification system. As the P3 gene is thought to be involved in viral replication, systemic infection, pathogenicity, and overcoming resistance, knowledge of the P3 gene sequences of SMV and other potyviruses would be useful in efforts to know the genetic relationships among them and control the disease. P3 gene sequences were obtained from representative isolates of the above-mentioned 16 SMV strains and were compared with other SMV strains and 16 Potyvirus species from the National Center for Biotechnology GenBank database. The P3 genes from the 16 SMV isolates are composed of 1041 nucleotides, encoding 347 amino acids, and share 90.7-100% nucleotide （NT） sequence identities and 95.1-100% amino acid （AA） sequence identities. The P3 coding regions of the 16 SMV isolates share high identities （92.4-98.9% NT and 96.0-100% AA） with the reported Korean isolates, followed by the USA isolates （88.5-97.9% NT and 91.4-98.6% AA）, and share low identities （80.5-85.2% NT and 82.1-84.7% AA） with the reported HZ 1 and P isolates from Pinellia ternata. The sequence identities of the P3 genes between SMV and the 16 potyviruses varied from 44.4 to 81.9% in the NT sequences and from 21.4 to 85.3% in the AA sequences, respectively. Among them, SMV was closely related to Watermelon mosaic virus （WMV）, with 76.0-81.9% NT and 77.5-85.3% AA identities. In addition, the SMV isolates and potyvirus species were clustered into six distinct groups. All the SMV strains isolated from soybean were clustered in Group I, and the remaining species were clustered in other groups. A multiple sequence alignment analysis of the C-terminal regions indicated that the P3 genes within a species were highly conserved, whereas those among species were relatively variable.
基金funding from the European Union Next Generation EU(PIANO NAZIONALE DI RIPRESA E RESILIENZA(PNRR)–MISSIONE 4 COMPONENTE 2,INVESTIMENTO 1.4–D.D.103217/06/2022,CN00000022)。
文摘A headspace solid-phase microextraction-gas chromatography-mass spectrometry(HS-SPME/GC-MS)method was used to study the volatile organic compounds(VOCs)associated with the differential immune response of tomato plants infected with the recombinant strain of potato virus Y(PVY^(C)-to),necrogenic to tomato.Analysis was carried out in UC82(UC),a virus susceptible tomato variety,comparing the same UC plants grafted or not onto a virus tolerant tomato ecotype,Manduria(Ma);the three types of samples used for the GC-MS analysis were mock-inoculated UC/Ma plants,UC/Ma+PVY^(C)-to and UC+PVY^(C)-to plants;the VOCs obtained were 111.Results from symptomatic PVY^(C)-to-infected UC plants showed a VOCs composition enriched in alcohols,fatty acid derivates,benzenoids,and salicylic acid derivatives,while in mock-inoculated UC/Ma plants VOCs were mainly characterized by methyl ester compounds.The VOC profile was in line with RNAseq data analyses,denoting that PVY^(C)-to viral RNA accumulation and disease symptoms induce the specific transcriptional activation of genes involved in VOCs biosynthesis.Furthermore,principal component analysis highlighted that VOCs of PVY^(C)-to-infected and mock-inoculated grafted plants were much closer each other than that of symptomatic PVY^(C)-to-infected non-grafted UC plants.These results suggest that VOCs profiles of tomato plants are related to the viral RNA accumulation,disease intensity and graft-derived tolerance to PVY^(C)-to infection.
基金supported by the National Natural Science Foundation of China(31770164)Jiangsu Province’s Innovation Program(JSSCTD202142).
文摘To fight against invasion by pathogens,plants have evolved an elaborate innate immune system,of which the nucleotide-binding domain leucine-rich repeat-containing receptor(NLR)acts as the sensor and immune executor.Potyviruses,comprising one of the largest genera of plant viruses,cause severe crop yield losses worldwide.Inherited crop resistance to potyviruses can be used in breeding and plant transgenesis to control disease development.This review summarizes achievements in mapping and cloning NLR genes conferring dominant resistance against potyvirus in the families Fabaceae,Solanaceae,Brassicaceae,and Cucurbitaceae.It compares mechanisms of potyviral protein recognition and downstream signaling employed by NLRs and discusses strategies for exploiting NLRs to better control diseases caused by potyviruses.
文摘Potyviruses are major constraints to grain legume production by causing significant yield losses. Potyviruses infecting Bambara groundnut (Vigna subterranea) were investigated in Burkina Faso. Leaf samples collected from three agroclimatic zones were subjected to RT-PCR and sequence analyses. Of a total of 135 samples, 36 (26.67%) were detected positive in RT-PCR tests using potyvirus universal primers. Analysis of full coat protein (cp) sequences from 24 isolates revealed the occurrence of three groups of Bambara groundnut-infecting potyviruses. Virus isolates in group 1 shared 94.5% - 100% nucleotide (nt) identity with CABMV whereas those in group 2 and group 3 were distantly related Bean common necrosis virus (BCMNV) and Passiflora virus Ugandan which were their respective closest potyviruses. Group 2 shared 77.1% nt and 78.8% - 79.9% aa identity with BCMNV and group 3 shared 77.3% - 78.3% nt and 80.7% - 81.5% aa identity with Passiflora virus Ugandan. All three groups were confirmed by phylogenetic analyses. Taking into account potyvirus demarcation criteria, group 1 isolates belonged to CABMV species. Group 2 and group 3 were assigned to a potentially new potyviruses species and designated Bambara groundnut potyvirus 1 (BGPV1) and Bambara groundnut potyvirus 2 (BGPV2).
基金supported by National Natural Science Foundation of China(31860490)YNTC funds(2023530000241007 and 2017YN02)+1 种基金Yunnan Daguan Lab(YNDG202302ZY01)CLZ is supported by the Postdoctoral Fellowship Program of CPSF under grant number GZC20241527。
文摘Recessive resistance mediated by mutations in the eukaryotic translation initiation factor 4E(eIF4E),has proven effective against diverse potyviruses and is extensively utilized in breeding programs.However,the rise of resistance-breaking(RB)strains and emerging potyviral species necessitates the development of more durable and broad-spectrum resistance strategies.In this study,our field survey in Yunnan,China,identified potato virus Y(PVY)RB isolates,as well as the prevalence of tobacco vein banding mosaic virus(TVBMV)and chilli veinal mottle virus(ChiVMV),in tobacco carrying the recessive va locus,which lacks the eIF4E1-S susceptibility gene,due to a chromosomal deletion.Protein interaction and viral infection assays demonstrated that both eIF4E1-S and eIFiso4E-T are used by PVY RB as susceptibility factors for infection,with the combined inactivation of these genes confering durable resistance.Similarly,the knockout of eIFiso4E-S,in the va genetic background,provided effective resistance to TVBMV and reduced susceptibility to ChiVMV.Notably,pyramiding mutations in eIFiso4E-S and eIFiso4E-T,in va tobacco,generated plants exhibiting robust,broad-spectrum resistance,to all three viruses,without compromising plant development.These findings underscore the potential of stacking eIF4E mutations to engineer durable,broad-spectrum resistance to potyviruses in tobacco,offering a promising strategy for crop improvement.
基金supported by grants from Ministry of Agriculture and Rural Affairs of China(2018YFD020062)the Chinese Universities Scientific Fund(2019TC064).
文摘Pennisetum plants(Pennisetum alopecuroides L.),displaying a dwarfing phenotype along with delayed flowering and mosaic symptom on leaves,were found in Beijing,China.Flexuous filamentous particles with a size of approximate 15×850 nm were observed in symptomatic leaves via transmission electron microscopy.Deep sequencing of small RNAs(sRNA)from symptomatic leaves and analysis of sRNA populations were then conducted to determine the genome sequence of the viral agent in diseased plant tissues.It showed that the viral agent had one positive-sense and single-stranded RNA genome,which consisted of 9717 nucleotides(nts)excluding poly(A)tail.The complete viral genome contained a large open reading frame,encoding a polyprotein of 3131 amino acids(aa).Sequence comparison and phylogenetic analysis demonstrated that the viral agent belonged to the genus Potyvirus in the family Potyviridae.In the cladogram it was most closely related to johnsongrass mosaic virus,sharing 72%nt and 65%aa sequence identity.This viral agent was provisionally named pennisetum alopecuroides mosaic virus(PalMV).Subsequently,it was confirmed that PalMV is the causal agent of this new disease in P.alopecuroides by Koch’s postulates and reverse transcription-polymerase chain reaction analysis.Moreover,maize,millet,wheat,sorghum and rice plants were experimentally infected by PalMV via rub inoculation.Consequently,we proposed that PalMV could be a potentially dangerous virus threating a wide range of cereal crops.
基金supported by grants from the National Natural Science Foundation of China(NSFC31720103912,31871933)+1 种基金‘Taishan Scholar’Construction Project(TS201712023)Funds of Shandong‘Double Tops’Program(SYL2017XTTD11).
文摘Coat protein(CP)is required for potyviruses to move and establish a systemic infection in plants.π-stackings formed by aromatic residues play critical roles in maintaining protein stability and functions.As we know,many aromatic residues located in the core region of potyvirus CPs are conserved.However,their roles in potyvirus infection remain largely unknown.Here,through analysis of the three-dimensional model of the tobacco vein banding mosaic virus(TVBMV;genus Potyvirus)CP,16 aromatic residues were predicated to formπ-stackings.The results of transient expression experiments demonstrated that deletion of any of these 16 aromatic residues reduced CP accumulation.Infectivity assays showed that deletion of any of these aromatic residues in the TVBMV infectious clone abolished cell-to-cell movement and reduced replication of the virus.Substitution of Y^(105) and Y^(147) individually with non-aromatic residues alanine or glycine reduced CP accumulation,virus replication,and abolished the ability of TVBMV to move intercellularly,while substitution of these two residues individually with aromatic residues phenylalanine or tryptophan,had no or little effect on CP accumulation and TVBMV systemic movement and replication.Similar results were obtained from the CP mutants of watermelon mosaic virus(WMV,genus Potyvirus).Taken together,our results demonstrate that multiple aromatic residues in CP are involved in potyvirus movement by formingπ-stackings to maintain CP accumulation.
基金supported by the grants from the National Natural Science Foundation of China(31801712)the Key Research and Development Program of Guangdong Province,China(2018B020202006)+1 种基金the Agricultural Competitive Industry Discipline Team Building Project of Guangdong Academy of Agricultural Sciences(202103TD and 202105TD)the Development Program for Guangdong Province Modern Agricultural Science and Technology Innovation Alliance(2020KJ113)。
文摘Viral diseases are among the most critical damaging factors that impose a global threat to the cucurbit industry.China is the world’s leading country for the production and consumption of cucurbits.Guangdong,a province in southern China dominated by the tropical and subtropical climate,favors the survival of different plant viruses and their vectors.Five main cucurbit crops showing various disease symptoms were surveyed and collected to identify viruses infecting cucurbits in Guangdong during 2018–2020.In the field,the incidence ranged from 5-30%,or even 60-100% in the case of severely infected cucurbits.A total of 357 symptomatic samples were collected and subsequently screened for cucurbit viruses by small RNA deep sequencing and assembly(sRSA).Seventeen virus species belonging to 10 genera were identified in the five main cucurbit crops.The most common viruses were papaya ringspot virus(PRSV;Potyvirus),zucchini tigre mosaic virus(ZTMV;Potyvirus),zucchini yellow mosaic virus(ZYMV;Potyvirus),and watermelon silver mottle virus(WSMoV;Orthotospovirus),with infection rates of 24.4,19.0,17.1,and 14.3%,respectively.Notably,the most prevalent viruses were melon yellow spot orthotospovirus(MYSV)in cucumber,PRSV in squash,cucumber green mottle mosaic virus(CGMMV;Tobamovirus)in bottle gourd,WSMoV in white gourd,and ZYMV in luffa.Mixed infections were prevalent,and the types of mixed infections varied substantially in different cucurbit crops.Moreover,the full-length nucleotide sequences of watermelon green mottle mosaic virus(WGMMV),CGMMV,and watermelon virus A(WVA;Wamavirus)identified in bottle gourd were cloned and analyzed.This study is the first reporting WGMMV infecting bottle gourd in China mainland.In summary,the results demonstrate that in Guangdong,the most prevalent viruses belong to potyviruses,orthotospoviruses,and tobamoviruses groups.The findings will facilitate agricultural researchers and farmers to plan and implement effective disease control strategies aiming at timely detection and management of cucurbit-infecting viral pathogens.
