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Garlic viral complex: identification of Potyviruses and Carlavirus in Central Brazil
FAJARDO, THOR V. M.;NISHIJIMA, MARTA;BUSO, JOSé A.;TORRES, ANT?NIO C.;áVILA, ANT?NIO C.;RESENDE, RENATO O.;
Fitopatologia Brasileira , 2001, DOI: 10.1590/S0100-41582001000300007
Abstract: garlic viruses often occur in complex infections in nature. in this study, a garlic virus complex, collected in fields in brazil, was purified. rt-pcr was performed using specific primers designed from the consensus regions of the coat protein genes of onion yellow dwarf virus, a garlic strain (oydv-g) and leek yellow stripe virus (lysv). cdna of garlic common latent virus (gclv) was synthesized using oligo-dt and random primers. by these procedures individual garlic virus genomes were isolated and sequenced. the nucleotide sequence analysis associated with serological data reveals the presence of two potyvirus oydv-g and lysv, and gclv, a carlavirus, simultaneously infecting garlic plants. deduced amino acid sequences of the brazilian isolates were compared with related viruses reported in different geographical regions of the world. the analysis showed closed relations considering the brazilian isolates of oydv-g and gclv, and large divergence considering lysv isolate. the detection of these virus species was confirmed by specific reactions observed when coat protein genes of the brazilian isolates were used as probes in dot-blot and southern blot hybridization assays. in field natural viral re-infection of virus-free garlic was evaluated.
Garlic viral complex: identification of Potyviruses and Carlavirus in Central Brazil  [cached]
FAJARDO THOR V. M.,NISHIJIMA MARTA,BUSO JOSé A.,TORRES ANT?NIO C.
Fitopatologia Brasileira , 2001,
Abstract: Garlic viruses often occur in complex infections in nature. In this study, a garlic virus complex, collected in fields in Brazil, was purified. RT-PCR was performed using specific primers designed from the consensus regions of the coat protein genes of Onion yellow dwarf virus, a garlic strain (OYDV-G) and Leek yellow stripe virus (LYSV). cDNA of Garlic common latent virus (GCLV) was synthesized using oligo-dT and random primers. By these procedures individual garlic virus genomes were isolated and sequenced. The nucleotide sequence analysis associated with serological data reveals the presence of two Potyvirus OYDV-G and LYSV, and GCLV, a Carlavirus, simultaneously infecting garlic plants. Deduced amino acid sequences of the Brazilian isolates were compared with related viruses reported in different geographical regions of the world. The analysis showed closed relations considering the Brazilian isolates of OYDV-G and GCLV, and large divergence considering LYSV isolate. The detection of these virus species was confirmed by specific reactions observed when coat protein genes of the Brazilian isolates were used as probes in dot-blot and Southern blot hybridization assays. In field natural viral re-infection of virus-free garlic was evaluated.
Genome organization and phylogenetic tree analysis of Garlic virus E, a new member of genus Allexivirus
Jiong Chen,Jianping Chen
Chinese Science Bulletin , 2002, DOI: 10.1360/02tb9006
Abstract: The complete sequence of an Allexivirus isolated from garlic plants in Yuhang City, Zhejiang Province, China had been determined. The single-strand, positive RNA genome was 8451 nucleotides in length excluding poly(A) tail. The genome organization of this virus was similar to that of the other Allexiviruses but only with 62.8%–64.8% nucleotide acid identities. The amino acid sequences of proteins encoded by ORF1-6 shared 67.6%–78.5%, 55.4%–66.2%, 56.7%–66.4%,40.3%–55.6%,66.3%–79.7%and 52.2%–68.8% identities with those of the others respectively. The homology range between it and the other Allexiviruses was similar to that between the other distinct species in this genus. A more comprehensive comparison using all available CP amino acid sequences showed that it shared only 63.9%–79.8% amino acids identical with the others. Therefore, it had been considered as a new member of the genus, named as garlic virus E (GarV-E). Phylogenetic analysis confirmed GarV-E as a distinct member and the correct names and classification of some members of genus Allexivirus were also discussed.
Porocephalus species (Pentastomida) infecting Boa constrictor (Boidae) and Lachesis muta (Viperidae) in northeastern Brazil
Waltécio de Oliveira Almeida,Felipe Silva Ferreira,Miriam Camargo Guarnieri,Samuel Vieira Brito
Biotemas , 2008,
Abstract: Brazil has a great diversity of snakes, but there are few published works concerning parasitism in these animals. The present paper examined pulmonary infection by pentastomids in large snakes from northeastern Brazil, including six specimens of Boa constrictor and two examples of Lachesis muta from the Serpentarium of the Federal University of Pernambuco (UFPE), Brazil, all of which were collected in the Atlantic Coastal Forest. One specimen of B. constrictor was infected by Porocephalus sp. (intensity of infection 5.0) and one specimen of L. muta was infected by P. stilesi (intensity of infection 15.0).
Rickettsia species infecting Amblyomma ticks from an area endemic for Brazilian spotted fever in Brazil
Guedes, Elizangela;Leite, Romário Cerqueira;Pacheco, Richard Campos;Silveira, Iara;Labruna, Marcelo Bahia;
Revista Brasileira de Parasitologia Veterinária , 2011, DOI: 10.1590/S1984-29612011000400009
Abstract: this study reports rickettsial infection in amblyomma cajennense and amblyomma dubitatum ticks collected in an area of the state of minas gerais, brazil, where brazilian spotted fever is considered endemic. for this purpose, 400 adults of a. cajenennse and 200 adults of a. dubitatum, plus 2,000 larvae and 2,000 nymphs of amblyomma spp. were collected from horses and from the vegetation. the ticks were tested for rickettsial infection through polymerase chain reaction (pcr) protocols targeting portions of three rickettsial genes (glta, ompa, and ompb). only two free-living a. cajennense adult ticks, and four pools of free-living amblyomma spp. nymphs were shown to contain rickettsial dna. pcr products from the two a. cajennense adult ticks were shown to be identical to corresponding sequences of the rickettsia rickettsii strain sheila smith. dna sequences of glta-pcr products of the four nymph pools of amblyomma spp. revealed a new genotype, which was shown to be closest (99.4%) to the corresponding sequence of rickettsia tamurae. our findings of two r. rickettsii-infected a. cajennense ticks corroborate the endemic status of the study area, where human cases of bsf were reported recently. in addition, we report for the first time a new rickettsia genotype in brazil.
Distinct Leishmania Species Infecting Wild Caviomorph Rodents (Rodentia: Hystricognathi) from Brazil  [PDF]
Renata Cássia-Pires,Mariana C. Boité,Paulo S. D'Andrea,Heitor M. Herrera,Elisa Cupolillo,Ana Maria Jansen,André Luiz R. Roque
PLOS Neglected Tropical Diseases , 2014, DOI: 10.1371/journal.pntd.0003389
Abstract: Background Caviomorph rodents, some of the oldest Leishmania spp. hosts, are widely dispersed in Brazil. Despite both experimental and field studies having suggested that these rodents are potential reservoirs of Leishmania parasites, not more than 88 specimens were analyzed in the few studies of natural infection. Our hypothesis was that caviomorph rodents are inserted in the transmission cycles of Leishmania in different regions, more so than is currently recognized. Methodology We investigated the Leishmania infection in spleen fragments of 373 caviomorph rodents from 20 different species collected in five Brazilian biomes in a period of 13 years. PCR reactions targeting kDNA of Leishmania sp. were used to diagnose infection, while Leishmania species identification was performed by DNA sequencing of the amplified products obtained in the HSP70 (234) targeting. Serology by IFAT was performed on the available serum of these rodents. Principal findings In 13 caviomorph rodents, DNA sequencing analyses allowed the identification of 4 species of the subgenus L. (Viannia): L. shawi, L. guyanensis, L. naiffi, and L. braziliensis; and 1 species of the subgenus L. (Leishmania): L. infantum. These include the description of parasite species in areas not previously included in their known distribution: L. shawi in Thrichomys inermis from Northeastern Brazil and L. naiffi in T. fosteri from Western Brazil. From the four other positive rodents, two were positive for HSP70 (234) targeting but did not generate sequences that enabled the species identification, and another two were positive only in kDNA targeting. Conclusions/Significance The infection rate demonstrated by the serology (51.3%) points out that the natural Leishmania infection in caviomorph rodents is much higher than that observed in the molecular diagnosis (4.6%), highlighting that, in terms of the host species responsible for maintaining Leishmania species in the wild, our current knowledge represents only the “tip of the iceberg.”
Spread of viruses in garlic fields cultivated under different agricultural production systems in Brazil
Fayad-André, Michelle de S.;Dusi, André Nepomuceno;Resende, Renato Oliveira;
Tropical Plant Pathology , 2011, DOI: 10.1590/S1982-56762011000600001
Abstract: samples from four regions, representing 76% of the garlic growing area in brazil, were tested by rt-pcr for the presence of onion yellow dwarf virus (oydv), leek yellow stripe virus (lysv), garlic common latent virus (gclv), garlic virus c (garv-c), garlic virus d (garv-d) and garlic mite-borne filamentous virus (garmbfv). the samples (352 bulbs) represented five agricultural systems: traditional common garlic (cg), virus-free common garlic (vfcg), non-vernalized noble garlic (nvngsg) and vernalized noble garlic cultivated by small growers (vngsg), and vernalized noble garlic adopted by major growers (vngmg). multiple infections were detected in 22% of the samples. potyvirus species were present in all regions. lysv prevailed over oydv while the carlavirus gclv was less prevalent. garv-c and garmbfv were the most prevalent among the allexivirus species. the nvng production system had a higher prevalence of lysv and garv-c. the cg production system, that uses less technology, had the highest prevalence for all species, especially lysv that prevailed in 94% of the samples. overall, the regions with higher technological input employing better quality seeds had the lowest viral prevalence for all species. this monitoring provides information to establish a strategy to raise the phytosanitary quality and the national productivity of garlic.
A new species of pentastomida infecting Tropidurus hispidus (Squamata: Tropiduridae) from Caatinga in Northeastern Brazil
Almeida, WO.;Freire, EMX.;Lopes, SG.;
Brazilian Journal of Biology , 2008, DOI: 10.1590/S1519-69842008000100029
Abstract: this article describes a new species of brazilian raillietiella sambon, 1910 from lungs of tropidurus hispidus (spix, 1825). between july and october 2005 eighteen specimens of t. hispidus were actively captured with elastic rubber slings in granite outcrops (lajeiros) (06° 59? s and 39° 31? w) from caatinga formations in the municipality of farias brito, state of ceará, northeastern brazil. one female and one male of t. hispidus had lungs infected by raillietiella mottae sp. nov. (prevalence 11.1% and mean intensity of infection 6.0 ± 1.4, range 5-7). the parasite?s main diagnostic characteristics include the dimensions of sharp hooks and strongly curved or "c-shaped" male copulatory spicules with knob-like posterior projection from the base towards the inner curvature of the spicule.
Detec??o de allexivírus em primórdios foliares de alho via RT-PCR
Nascimento, Robson José do;Pio-Ribeiro, Gilvan;Santos, Roseane Cavalcanti dos;Melo Filho, Péricles de Albuquerque;
Summa Phytopathologica , 2008, DOI: 10.1590/S0100-54052008000300014
Abstract: cloves crop is a routinely practice often used in procedures for detecting allexiviruses in garlic bulbs to obtainment foliar tissue to be analyzed by serological and/or molecular tests. the availability of the plants under greenhouse implies is expenses with the maintenance and requires abaut 30 days. in areas free of these viruses, there is also the risk of their introduction and dissemination. this study presents an adjustment of protocol aiming a fast detection of allexiviruses, using primordial leaves. cloves of consumption-garlic, from rio grande do sul, brazil, and imported from argentina were dissected for obtaining primordial leaves and total rna extraction, using 0,1g of tissue of each sample. rt-pcr reactions were performed with a pair of primers able to amplify a 500 bp fragment, corresponding to the internal region of the coat protein gene from several species of allexivirus genus. a band in the expected height (500 pb) was visualized in agarose gels and further confirmed using southern blot test and by sequencing as garlic virus c (garv-c, ay170322.1). total rna obtained from foliar primordia of cloves and its use in rt-pcr analysis is an economic, fast and secure methodology for allexivirus detection in garlic bulbs.
Genetic diversity of begomovirus infecting tomato and associated weeds in Southeastern Brazil
AMBROZEVICIUS, LUCIANA P.;CALEGARIO, RENATA F.;FONTES, ELIZABETH P.B.;CARVALHO, MURILO G. DE;ZERBINI, F. MURILO;
Fitopatologia Brasileira , 2002, DOI: 10.1590/S0100-41582002000400006
Abstract: the genetic diversity of begomovirus isolates from tomato (lycopersicon esculentum) fields in the southeastern region of brazil was analyzed by direct sequencing of pcr fragments amplified by using universal oligonucleotides for the begomovirus dna-a, and subsequent computer-aided phylogenetic analysis. samples of tomato plants and associated weeds showing typical symptoms of virus infection were collected at seven locations in the states of minas gerais, espírito santo and rio de janeiro. a total of 137 out of 369 samples were infected with a begomovirus based on pcr analysis. phylogenetic analysis indicated a high degree of genetic diversity among begomoviruses infecting tomatoes in the sampled area. one species (tomato chlorotic mottle virus, tcmv) occurs predominantly in minas gerais, whereas in rio de janeiro and espírito santo a distinct species, not yet fully characterized, predominates. phylogenetic analysis further indicates the presence of an additional four possible new species. this high degree of genetic diversity suggests a recent transfer of indigenous begomovirus from wild hosts into tomatoes. the close phylogenetic relationship verified between begomovirus infecting tomato and associated weeds favors this hypothesis.
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