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1.
The complete genome of a novel bipartite begomovirus (genus Begomovirus, family Geminiviridae) was cloned from a severely diseased yellow Peruvian chili pepper (Capsicum baccatum cv. Pendulum) plant collected in the department of La Libertad, Northern Peru and full‐length sequenced. The two genomic components share a common region of 156 nucleotides with a 100% sequence identity. Analysis of the genome organisation and phylogenetic comparisons revealed that the virus is a typical New World begomovirus. The closest related begomovirus, an isolate of Tomato yellow vein streak virus (ToYVSV), shared only 76.8% nucleotide sequence identity for the DNA‐A component. Therefore, following species demarcation criteria of the International Committee on Taxonomy of Viruses, this virus isolate belongs to a new begomovirus species for which the name pepper leafroll virus (PepLRV) is proposed. Pepper plants infected with the cloned PepLRV isolate developed leaf roll symptoms similar to those observed in field‐infected plants suggesting this virus as the causal agent of the disease syndrome observed in the field. Widespread occurrence of PepLRV throughout Peru was demonstrated, infecting plants of diverse cultivated species such as tomato, pepper, common and pallar beans, and of the weed species Nicandra physaloides. Low genetic diversity was observed among PepLRV isolates present in this country with no evident geographical or temporal structure of the population, typical of a recent founder effect. This is the first report of a begomovirus infecting pepper and bean crops in Peru.  相似文献   

2.
The spectrum of entomophthoroid fungal species parasitising aphids on cereal crops and a study of the phenology and prevalence of these pathogens were investigated in Argentina. The studies were conducted at six different sites cultivated with crops of Triticum aestivum (wheat), Avena sativa (oats) and Sorghum bicolor (sorghum) during two consecutive years. Entomopathogenic fungi from the new phylum Entomophthoromycota were recorded from six aphid species on cereals in Argentina: Rhopalosiphum maidis, Rhopalosiphum padi, Rhopalosiphum rufiabdominalis, Schizaphis graminum, Sitobion avenae and Sipha maydis. Three species of entomophthoroid fungi were found infecting these aphid species: Pandora neoaphidis, Zoophthora radicans (Entomophthorales: Entomophthoraceae) and Neozygites fresenii (Neozygitales: Neozygitaceae). Entomophthoroid fungal infections occurred mostly in autumn–winter seasons (March–August), and coincided with periods of high relative humidity and comparatively low temperatures. This study represents the first base‐line characterisation of entomophthoroid fungi infecting aphids on cereal crops in Argentina.  相似文献   

3.
Tomato leaf curl Hainan virus (ToLCHnV) was previously reported as a distinct begomovirus infecting tomato in Hainan, China. To investigate the infectivity of ToLCHnV, an infectious clone of ToLCHnV‐[CN: HaNHK7] was constructed and agro‐inoculated into Solanum lycopersicum, Nicotiana benthamiana, Nicotiana glutinosa, Petunia hybrida, Cucumis sativus, Solanum melongena and Capsicum annuum plants; it induced severe leaf curling and crinkling symptoms in these plant species except C. sativus, S. melongena and C. annuum. The induced symptoms were compared with those induced by Papaya leaf curl China virus.  相似文献   

4.
Yellow mosaic disease (YMD) is one of the most important diseases affecting different leguminous crops and causes significant yield losses in Indian sub‐continent. Eight different bipartite begomovirus species are known to cause YMD in more than 10 leguminous crops. These species are collectively known as legume yellow mosaic viruses (LYMVs), and their full genomes have been characterised except for Dolichos yellow mosaic virus (DoYMV). In this study, full genome of DoYMV isolate (KJ481204 and KJ481205) infecting dolichos has been characterised. The DNA‐A of DoYMV consists of 2761 nucleotides and DNA‐B of 2733 nucleotides with a genome organisation typical of Old World bipartite begomoviruses. Nucleotide identity of DNA‐B (KJ481205) of DoYMV with DNA‐B of other legumoviruses was 57.5–61.0%. Both components contain a nonanucleotide and conserved inverted repeat sequences with the potential to form a stem‐loop. Nucleotide identity of common region of DoYMV was 90.3%, above the threshold nucleotide identity (>85%) for considering a DNA‐B molecule as cognate of DNA‐A of a begomovirus. Four recombination events in DNA‐A and two in DNA‐B of DoYMV isolate were detected. Mungbean yellow mosaic virus, Rhynchosia yellow mosaic virus and Horsegram yellow mosaic virus were identified as probable parents.  相似文献   

5.
During 2015–2016, wooden and herbaceous plants growing in parks, boulevards, fields, gardens and forests in Khuzestan province, southwestern Iran, were visually inspected for symptoms resembling phytoplasma. Fifty‐one symptomatic samples from nine different species and one symptomless sample from each plant were collected. Leaf midribs, petioles and the parts of stem cambium were separated and freeze‐dried. Total DNA was extracted using CTAB‐based method and tested for phytoplasma using a nested PCR assay. The expected size amplicons of 16S rDNA were sequenced and compared to those of reference phytoplasmas by BLASTn search and phylogenetic analysis. The consensus 16S rDNA sequence of the detected phytoplasma in narrow cattail related to reference phytoplasma group 16SrVI, “Candidatus Phytoplasma trifolii” while in the other plants were related to reference phytoplasma subgroup 16SrII–D, “Candidatus Phytoplasma aurantifolia.” All isolates showed 98%–99% sequence identity to members of their reference groups. To our knowledge, this is the first report of “Candidatus Phytoplasma aurantifolia”‐related strains infecting the plants of Acacia salicina, Alternanthera ficoidea, Melaleuca citrine, Citrus aurantium throughout the world and Celosia christata in Iran. Furthermore, this study is the first to report the association of a “Candidatus Phytoplasma trifolii”‐related strain with Typha angustifolia worldwide.  相似文献   

6.
Comparative genomic analysis revealed differences in the lipopolysaccharide (LPS) biosynthesis gene cluster between the Rubus‐infecting strain ATCC BAA‐2158 and the Spiraeoideae‐infecting strain CFBP 1430 of Erwinia amylovora. These differences corroborate rpoB‐based phylogenetic clustering of E. amylovora into four different groups and enable the discrimination of Spiraeoideae‐ and Rubus‐infecting strains. The structure of the differences between the two groups supports the hypothesis that adaptation to Rubus spp. took place after species separation of E. amylovora and E. pyrifoliae that contrasts with a recently proposed scenario, based on CRISPR data, in which the shift to domesticated apple would have caused an evolutionary bottleneck in the Spiraeoideae‐infecting strains of E. amylovora which would be a much earlier event. In the core region of the LPS biosynthetic gene cluster, Spiraeoideae‐infecting strains encode three glycosyltransferases and an LPS ligase (Spiraeoideae‐type waaL), whereas Rubus‐infecting strains encode two glycosyltransferases and a different LPS ligase (Rubus‐type waaL). These coding domains share little to no homology at the amino acid level between Rubus‐ and Spiraeoideae‐infecting strains, and this genotypic difference was confirmed by polymerase chain reaction analysis of the associated DNA region in 31 Rubus‐ and Spiraeoideae‐infecting strains. The LPS biosynthesis gene cluster may thus be used as a molecular marker to distinguish between Rubus‐ and Spiraeoideae‐infecting strains of E. amylovora using primers designed in this study.  相似文献   

7.
Argemone mexicana L. (Papaveraceae), a tropical annual weed, is known to be phytotoxic to many crop species. This study was designed to examine the possible impact of A. mexicana on root‐infecting fungi, changes in fungal community structure and the growth of tomato. A. mexicana decaying shoots in soil provided a marked decrease in the infectivity of Fusarium solani and Rhizoctonia solani but Macrophomina phaseolina remained unaffected. Plant height and shoot growth of tomato plants increased markedly though high concentration of A. mexicana (5% w/w) was deleterious to tomato plants. General species diversity of soil fungal communities increased in the amended soils over the controls and greater increase in diversity occurred at higher concentrations of decaying A. mexicana. Likewise, equitability and richness components of diversity increased in treatments compared to controls but declined with increasing sampling period. Aspergillus nidulans, Cephaliophora irregularis, Drechslera halodes, Paecilomyces lilacinus and Trichoderma viride were isolated exclusively from the amended soils. Aqueous extract of A. mexicana when applied in soil greatly suppressed all three of the above root‐infecting fungi, and at lower concentration actually enhanced plant growth. The influence of different levels of N‐fertilization with NH4NO3 on the modification of the effect of decaying A. mexicana on root‐infecting fungi was also investigated. N‐fertilization to some extent alleviated the phytotoxicity to tomato plants while suppressing the root‐infecting fungi. A. mexicana in conjunction with Pseudomonas aeruginosa, a plant growth‐promoting rhizobacterium, significantly suppressed root‐infecting fungi with concomitant increase in plant growth. Whereas P. aeruginosa was reisolated from the rhizosphere and inner root tissues of tomato, its population slightly declined in the amended soil but not to an extent that could reduce the biocontrol and growth promoting potential of the bacterium.  相似文献   

8.
G. Babaie    B. Khatabi    H. Bayat    M. Rastgou    A. Hosseini    G. H. Salekdeh 《Journal of Phytopathology》2007,155(6):368-372
During field surveys in 2004, ornamental and weed plants showing symptoms resembling those caused by phytoplasmas were observed in Mahallat (central Iran). These plants were examined for phytoplasma infections by polymerase chain reaction (PCR) assays using universal phytoplasma primers directed to ribosomal DNA (rDNA). All affected plants gave positive results. The detected phytoplasmas were characterized and differentiated through restriction fragment length polymorphism (RFLP) and sequence analysis of PCR‐amplified rDNA. The phytoplasmas detected in diseased Asclepias curassavica and Celosia argentea were identified as members of clover proliferation phytoplasma group (16SrVI group) whereas those from the remaining plants examined proved to be members of aster yellow phytoplasma group (16SrI group) (‘Candidatus Phytoplasma asteris’). In particular, following digestion with AluI, HaeIII and HhaI endonucleases, the phytoplasma detected in Limonium sinuatum showed restriction profiles identical to subgroup 16SrI‐C; phytoplasmas from Gomphocarpus physocarpus, Tanatacetum partenium, Lactuca serriola, Tagetes patula and Coreopsis lanceolata had the same restriction profiles as subgroup 16SrI‐B whereas Catharanthus roseus‐ and Rudbeckia hirta‐infecting phytoplasmas showed restriction patterns of subgroup 16SrI‐A. This is the first report on the occurrence of phytoplasma diseases of ornamental plants in Iran.  相似文献   

9.
Begomoviruses (whitefly‐transmitted, single‐stranded DNA plant viruses) are among the most damaging pathogens causing epidemics in economically important crops worldwide. Besides cultivated plants, many weed and wild hosts act as virus reservoirs where recombination may occur, resulting in new species. The aim of this study was to further characterise the diversity of begomoviruses infecting two major weed genera, Sida and Leonurus. Total DNA was extracted from samples collected in the states of Rio Grande do Sul, Paraná and Mato Grosso do Sul during the years 2009–2011. Viral genomes were enriched by rolling circle amplification (RCA), linearised into unit length genomes using various restriction enzymes, cloned and sequenced. A total of 78 clones were obtained: 37 clones from Sida spp. plants and 41 clones from Leonurus sibiricus plants. Sequence analysis indicated the presence of six bipartite begomovirus species and two alphasatellites. In Sida spp. plants we found Sida micrantha mosaic virus (SiMMV), Euphorbia yellow mosaic virus (EuYMV), and three isolates that represent new species, for which the following names are proposed: Sida chlorotic mottle virus (SiCMoV), Sida bright yellow mosaic virus (SiBYMV) and Sida golden yellow spot virus (SiGYSV), an Old World‐like begomovirus. L. sibiricus plants had a lower diversity of begomoviruses compared to Sida spp., with only Tomato yellow spot virus (ToYSV) and EuYMV (for the first time detected infecting plants of the genus Leonurus) detected. Two satellite DNA molecules were found: Euphorbia yellow mosaic alphasatellite, for the first time detected infecting plants of the genus Sida, and a new alphasatellite associated with ToYSV in L. sibiricus. These results constitute further evidence of the high species diversity of begomoviruses in non‐cultivated hosts, particularly Sida spp.  相似文献   

10.
The natural occurrence of entomophathogenic fungi infecting spittlebugs (Hemiptera: Cercopidae) considered serious pests to pasture grasses and crops in Argentina was investigated during summer?autumn (December to May) from 2013 to 2016. Adults and nymphs of spittlebugs were collected from Sorghum halepense and Setaria parviflora var. parviflora in San Miguel de Tucumán, Tucumán province. The entomopathogenic fungal species were characterized on the basis of morphological keys and molecular techniques. Microscopic characters were described from material mounted in lactophenol/aceto‐orcein (1% w/v), and the amplification of the fungal SSU rDNA was carried out using the universal primers nu‐SSU‐0021‐5′ and nu‐SSU‐1780‐3′. Summarized information about occurrence of fungal infections on spittlebugs populations is provided. This study reports for the first time the occurrence of the genus Pandora infecting adults of the economically important spittlebugs Deois (Deois) mourei, D. (D.) knoblauchii, Isozulia christenseni christenseni and Notozulia entreriana from Argentina expanding the host range and geographical distribution of entomophthoralean fungi.  相似文献   

11.
Whitefly transmitted begomoviruses (family Geminiviridae) are the major reason for significant yield losses of dicotyledonous crops in tropics and subtropics. Okra (Abelmoschus esculentus) is one of the important vegetable crops, and leaf curl disease caused by geminiviruses is the most important limiting factor for its production in Pakistan. Here, we report a new species of okra‐infecting begomovirus in south‐eastern region of Pakistan and the name Okra enation leaf curl virus (OELCuV) complex is proposed. This okra enation leaf curl disease complex (OELCuD) in Pakistan is found to be associated with Ageratum conyzoides symptomless alphasatellite (AConSLA). All efforts to clone the betasatellite were unsuccessful. Comprehensive sequence analyses suggest that intermalvaceous recombination between okra and cotton‐infecting begomoviruses resulted in the evolution of the new species. Surprisingly, Bhendi yellow vein mosaic virus (BYVMV) which has not been reported previously from Pakistan is the major parent while Cotton leaf curl Multan virus (CLCuMV) acts as a distant parent of the virus. Comparative recombination analysis also reveals that okra‐infecting begomoviruses from south and north‐western India is causing OELCuD in the Pakistan by recombining with CLCuMV at the Rep (1964–1513 nts). Recombination is common among geminiviruses and recombining of BYVMV and CLCuMV resulted in a new species: OELCuV. To the best of our knowledge, this evolution of a new species of okra‐infecting begomovirus is the first report of intermalvaceous recombination where Rep acts as the target region.  相似文献   

12.
Dolichos yellow mosaic disease (DYMD) affects the production of dolichos in South Asia. Diseased plants produce characteristic bright yellow mosaic patches on the leaves and early infections cause reductions in yield. The putative dolichos yellow mosaic virus (DoYMV) was transmitted poorly (maximum 18.3% transmission) by the whitefly, Bemisia tabaci. DoYMV has a narrow host range and infected only Lablab purpureus and L. purpureus var. typicum out of the 36 species tested. Virus was detected using monoclonal antibodies in a triple‐antibody sandwich enzyme‐linked immunosorbent assay and by PCR. Complete DNA‐A components of DoYMV isolates from Mysore and Bangalore, South India, were sequenced, but several attempts to identify DNA‐B and DNA‐β were unsuccessful. DoYMV isolates shared DNA‐A nucleotide identities of 92.5–95.3% with previously described isolates from North India and Bangladesh. They were most similar to mungbean‐infecting begomoviruses at 61.6–64.4% of DNA‐A nucleotide identities. Phylogenetic analyses of DNA‐A sequences grouped the dolichos‐infecting and mungbean‐infecting begomoviruses into a distinct cluster away from begomoviruses infecting non‐leguminous plants in the Indian subcontinent. Antigenically, legume‐infecting begomoviruses were most similar to each other compared with non‐legume viruses. Collectively, these results indicate that legume‐infecting begomoviruses in the Indian subcontinent belonged to a distinct lineage of Old World begomoviruses.  相似文献   

13.
As a common feature of eukaryotic proteins, tandem amino acid repeat has been studied extensively in both animal and plant proteins. Here, a comparative analysis focusing on the proteins having tandem repeats was conducted in eight microsporidia, including four mammal‐infecting microsporidia (Encephalitozoon cuniculi, Encephalitozoon intestinalis, Encephalitozoon hellem and Encephalitozoon bieneusi) and four insect‐infecting microsporidia (Nosema apis, Nosema ceranae, Vavraia culicis and Nosema bombycis). We found that the proteins with tandem repeats were abundant in these species. The quantity of these proteins in insect‐infecting microsporidia was larger than that of mammal‐infecting microsporidia. Additionally, the hydrophilic residues were overrepresented in the tandem repeats of these eight microsporidian proteins and the amino acids residues in these tandem repeat sequences tend to be encoded by GC‐rich codons. The tandem repeat position within proteins of insect‐infecting microsporidia was randomly distributed, whereas the tandem repeats within proteins of mammal‐infecting microsporidia rarely tend to be present in the N terminal regions, when compared with those present in the C terminal and middle regions. Finally, a hypothetical protein EOB14572 possessing four tandem repeats was successfully characterized as a novel endospore wall protein, which colocalized with polar tube of N. bombycis. Our study provided useful insight for the study of the proteins with tandem repeats in N. bombycis, but also further enriched the spore wall components of this obligate unicellular eukaryotic parasite.  相似文献   

14.
The incidence of curly top disease on cultivated plants and weeds was investigated in Kerman Province (southeastern Iran) from October 2003 to November 2004. A total of 1186 samples were collected in fields of sugar beet and other crops as well as within commercial plastic houses. Curtovirus infection of four field crops, three vegetables and 11 weeds was verified by indirect enzyme‐linked immunosorbent assay (ELISA) using a polyclonal antibody. An undescribed curtovirus, tentatively designated Iranian beet curly top virus (IBCTV), was isolated from three symptomatic beet samples collected randomly in widely separated regions of south‐eastern, southern and central Iran and used for molecular studies. A 672 bp segment of the coat protein (CP) gene of each isolate was amplified by PCR and sequenced. The results showed that the three isolates shared 98.5–98.7% nucleotide homology with each other but only 72.1–76.5% with other members of the genus Curtovirus. IBCTV was also detected by PCR using specific primers in other samples of sugar beet, tomato, spinach, turnip and several weed species collected in different parts of Iran. These results indicated that IBCTV is the dominant curtovirus in Iran.  相似文献   

15.
Microsporidia are known opportunistic microorganisms and usually transmitted via the fecal–oral route. However, there is no information about human‐infecting microsporidia in wildlife in Iran. This study aimed to investigate and analyze human‐infecting microsporidia isolated from raccoons in north of Iran. Totally, 30 fecal samples were collected; then, DNA extraction was performed and specific fragments of the SSU rRNA gene of Enterocytozoon bieneusi and Encephalitozoon species were amplified. After amplification and sequencing the ITS, the results were compared to the GenBank database. Phylogenetic trees and network analysis were employed to explore probable relationships. E. bieneusi was the only detected microsporidia among samples. Genotyping showed the genotypes D, E, and RA in 15/18 (83.33%), 1/18 (5.55%), and 2/18 (11.11%) of samples, respectively. Novel genotypes RA1 and RA2 grouped together and apart from other genotypes. E. bieneusi genotypes D and E clustered with the genotypes previously reported from animals, humans, and environmental samples. Network analysis revealed six distinct sequence types among raccoon's isolates. This study demonstrated that E. bieneusi genotype D was the most prevalent microsporidia among raccoons. It seems that wildlife may play a role in dispersion of microsporidia spores.  相似文献   

16.
Recent studies identified three begomoviruses infecting soybean and bean crops in northwestern (NW) Argentina, bean golden mosaic virus (BGMV), a virus with high capsid protein identity with Sida mottle virus (SiMoV) and a possible new viral species (isolate A). Analysis of complete DNA‐A sequences confirmed that isolate A represents a new viral species for which the authors propose the name soybean blistering mosaic virus (SbBMV), whereas the SiMoV‐like virus is actually an isolate of tomato yellow spot virus (ToYSV). Molecular hybridisation‐based detection of the three begomoviruses was accomplished using a general probe obtained by mixing full‐length DNA‐A clones of the three begomoviruses and specific probes comprising part of the common region of each viral genome. These probes were used to test samples collected in NW Argentina from 2004 through 2007. Fifty‐three percent of the bean samples were infected with BGMV, 11.5% with ToYSV and 9% with SbBMV. For soybean samples, 33% were infected with SbBMV and 18% with ToYSV. BGMV was not detected in soybean. ToYSV was also detected in the wild species Abutilon theophrasti.  相似文献   

17.
Ectomycorrhiza is a mutualistic symbiosis formed between fine roots of trees and the mycelium of soil fungi. This symbiosis plays a key role in forest ecosystems for the mineral nutrition of trees and the biology of the fungal communities associated. The characterization of genes involved in developmental and metabolic processes is important to understand the complex interactions that control the ectomycorrhizal symbiosis. Agrobacterium‐mediated gene transfer (AMT) in fungi is currently opening a new era for fungal research. As whole genome sequences of several fungi are being released studies about T‐DNA integration patterns are needed in order to understand the integration mechanisms involved and to evaluate the AMT as an insertional mutagenesis tool for different fungal species. The first genome sequence of a mycorrhizal fungus, the basidiomycete Laccaria bicolor, became public in July 2006. Release of Laccaria genome sequence and the availability of AMT makes this fungus an excellent model for functional genomic studies in ectomycorrhizal research. No data on the integration pattern in Laccaria genome were available, thus we optimized a plasmid rescue approach for this fungus. To this end the transformation vector (pHg/pBSk) was constructed allowing the rescue of the T‐DNA right border (RB)–genomic DNA junctions in Escherichia coli. Fifty‐one Agrobacterium‐transformed fungal strains, picked up at random from a larger collection of T‐DNA tagged strains (about 500), were analysed. Sixty‐nine per cent were successfully rescued for the RB of which 87% were resolved for genomic integration sequences. Our results demonstrate that the plasmid rescue approach can be used for resolving T‐DNA integration sites in Laccaria. The RB was well conserved during transformation of this fungus and the integration analysis showed no clear sequence homology between different genomic sites. Neither obvious sequence similarities were found between these sites and the T‐DNA borders indicating non‐homologous integration of the transgenes. Majority (75%) of the integrations were located in predicted genes. Agrobacterium‐mediated gene transfer is a powerful tool that can be used for functional gene studies in Laccaria and will be helpful along with plasmid rescue in searching for relevant fungal genes involved in the symbiotic process.  相似文献   

18.
African swine fever virus (ASFV) infection in adult Ornithodoros porcinus (Murry 1877, sensu Walton 1979 ) ticks collected from warthog burrows in southern and East Africa was assessed using a duplex genomic amplification approach that is informative with respect to the invertebrate host species and infecting sylvatic cycle virus. DNA extracted from individual ticks was used as template for the simultaneous amplification of a C‐terminal 478‐bp ASFV p72 gene region and a ~313‐bp fragment of the tick mitochondrial 16S rRNA gene, under optimized reaction conditions. Within‐warthog burrow infection rates ranged from 0% to 43% using this approach, and phylogenetic analysis of 16S gene sequences revealed the presence of three geographically discrete O. porcinus lineages, but no support for subspecies recognition. False negatives are precluded by the inclusion of host species‐informative primers that ensure the DNA integrity of cytoplasmically located genome extracts. In addition, infection rate estimates are further improved as false positives arising from carry‐over contamination when performing a two‐step nested polymerase chain reaction are negated by the one‐step approach. Phylogenetic comparison of full‐length virus gene sequences with the partial C‐terminal p72 gene target confirmed the epidemiological utility of the latter in a sylvatic setting. The method is therefore of particular value in studies assessing the prevalence and diversity of ASFV in relation to the African sylvatic tick vector and holds potential for investigating the role of alternative tick species in virus maintenance and transmission.  相似文献   

19.
DNA sequence analysis of the nuclear ribosomal internal transcribed spacer region (ITS) was performed to determine phylogenetic relationship between 49 isolates of rusts infecting grain and forage legumes. Isolates were collected from different hosts and distinct geographic origins and represent eight species of Uromyces: U. anthyllidis, U. appendiculatus, U. ciceris‐arietini, U. minor, U. pisi, U. striatus, U. viciae‐fabae and U. vignae. ITS sequences revealed length polymorphisms and variation in DNA sequence that were used to characterize phylogenetic relationships by maximum parsimony, maximum likelihood and Bayesian analyses which in general agreed revealing the presence of four clearly distinct clades. Clade one included the isolates causing rust on chickpea, fenugreek and alfalfa. Clade two was composed by rust isolates of field clover and pea plants, while the third clade was formed by bean and cowpea isolates. Clade four was the largest and included all the rust isolates infecting faba bean. Within this clade, the highly supported subclusters of U. viciae‐fabae collected on Lens culinaris, U. viciae‐fabae collected on Vicia sativa and U. viciae‐fabae collected on Lathyrus palustris suggest an ongoing process of host specialization.  相似文献   

20.
Background Hepatitis B virus (HBV) is a public health problem worldwide and apart from infecting humans, HBV has been found in non‐human primates. Methods We subjected 93 non‐human primates comprising 12 species to ELISA screening for the serological markers HBsAg, antiHBs and antiHBc. Subsequently, we detected HBV DNA, sequenced the whole HBV genome and performed phylogenetic analysis. Results HBV infection was detected in gibbon (4/15) and orangutan (7/53). HBV DNA isolates from two gibbons and seven orangutans were chosen for complete genome amplification. We aligned the Pre‐S/S, Pre‐C/C and entire genomes with HBV sequences and performed phylogenetic analysis. The gibbon and orangutan viruses clustered within their respective groups. Conclusions Both geographic location and host species influence which HBV variants are found in gibbons and orangutans. Hence, HBV transmission between humans and non‐human primates might be a distinct possibility and additional studies will be required to further investigate this potential risk.  相似文献   

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