-
[show abstract]
[hide abstract]
ABSTRACT: DNA primers for banana bunchy top virus (BBTV) and for faba bean necrotic yellows virus (FBNYV) were constructed based on the nucleotide sequence of DNA component 1 of each virus that contains the viral putative replicase gene. Three pairs of primers for each virus were utilized for standard polymerase chain reaction (PCR) or immunocapture (IC) PCR amplification. DNA fragments of 439, 446, and 476 bp were amplified from extracts of BBTV-infected banana leaves, in vitro tissue culture, and viruliferous aphids. DNA fragments of 487, 931, and 1002 bp from extracts of FBNYV-infected faba bean plants and viruliferous vectors were also amplified. The amplified DNA fragments were identified by size, nucleotide sequence, and (or) hybridization analysis. Virus-specific DNA fragments were absent from amplified extracts of uninfected banana and faba bean tissues as well as from non-viruliferous aphids. The nucleotide sequence of the PCR-amplified major portion (923 nucleotides) of BBTV DNA component 1 of an Egyptian isolate has been determined. The sequence is 99% homologous to the Australian isolate of BBTV.
Canadian Journal of Plant Pathology 12/2009; December 1999(Vol. 21):326-337. · 0.88 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Faba bean necrotic yellows virus (FBNYV) belongs to a new group of plant viruses that have unusually small isometric virions and a multipartite ssDNA genome. It is the causal agent of some virus diseases affecting several food and fodder legumes in west Asia and north Africa. FBNYV is persistently transmitted by various aphid species of which Aphis craccivora appears to be the most significant natural vector. In attempts to obtain a better understanding of factors involved in FBNYV spread under field conditions, the interactions of the virus with A. craccivora and Acyrthosiphon pisum were studied. The two species were efficient vectors and very similar in their minimum acquisition (AAP) and minimum inoculation access feeding periods which ranged from 15 to 30min and 5–15min, respectively. Following an AAP of 72 h and daily serial transfers of individual aphids to single plants, many individuals retained and transmitted the virus throughout their life span (up to 32 days) but at erratic efficiencies. In this persistence experiment A. pisum was a more efficient vector than A. craccivora. For both aphid species no decrease in transmission efficiency was observed, suggesting that nymphs acquired large amounts of FBNYV virions which were not depleted in their hemocoel during the experiment. Based on log-pro-bit analysis, median latency period (LPso) values of 108.8h and 105.0h were calculated for FBNYV in A. craccivora and A. pisum, respectively. FBNYV was not lost during moults and was not passed on to the par-thenogenetic offspring by viruliferous adults. Aphids which acquired FBNYV as adults were strikingly poor vectors as compared to nymphs.ZusammenfassungFaba bean necrotic yellows virus (FBNYV) gehört einer neuen Gruppe von Pflanzenvireti an, die sich durch unge-wöhnlich kleine isometrische Virionen und einem multi-partiten einzelstrangigen DNA-Genom auszeichnen. Es ist der Verursacher einiger bedeutender Viruserkrankun-gen an Körner- und Futterleguminosen in Westasien und Nordafrika. FBNYV wird persistent von verschiedenen Blattlausarten übertragen, von denen Aphis craccivora der bedeutendste natürliche Vektor zu sein scheint. Um die an der Feldausbreitung des FBNYV beteiligten Fak-toren besser verstehen zu können, wurden die Interaktio-nen zwischen dem Virus und A. craccivora und Acyrthosiphon pisum untersucht. Sehr ähnlich waren sich die beiden Arten in der minimalen Akquisitionszeit (AAP) (15-30min) und minimalen Inokulationszeit (5-15min). Nach einer 72-stündigen AAP und einem täglichen Übersetzen von einzelnen Nymphen auf je eine Pflanze übertrugen viele Individuen das Virus fast lebenslänglich (bis zu 32 Tagen), jedoch mit wechseihafter Effizienz. In diesem Persistenzversuch war A. pisum ein effizienterer Vektor als A. craccivora. Für beide Blattlausarten wurde keine Abnahme der Übertragungseffizienz beobachtet, was den Schluß nahelegte, daß im Haemocoel der Nymphen große Vorräte an FBNYV-Virionen angelegt wurden, die sich während des Persistenzversuches nicht erschöpften. Aufgrund einer Log-Probit-Ana-lyse wurden mittlere Latenzperioden (LP50) von 108.8 h and 105.Oh für FBNYV in A. craccivora bzw. A. pisum ermittelt. FBNYV ging nicht während der Häutungen der Nymphen verloren und wurde nicht von virustragenden Adulten an die parthenogenetischen Nachkommen weitergegeben. Blattläuse, die FBNYV als Adulte aufnahmen, waren erhebhch schlechtere Vektoren als Nymphen.
Journal of Phytopathology 04/2008; 146(7):347 - 355. · 0.79 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Specific rabbit polyclonal antibodies against bacterially expressed coat protein of Faba bean necrotic yellows virus (FBNYV, genus Nanovirus) were produced using a recombinant DNA approach. The FBNYV capsid protein (CP) gene located on component 5 was cloned in an expression vector pQE-9 (Qiagen, QIAGEN Inc., Chatswortch, CA91311, USA). Expression of the CP with an N-terminal hexahistidine tag in Escheri- chia coli M15 cells was induced by adding isopropyl-3-D-1-thiogalactoside (IPTG) to a final concentration of 2 mM. About 8 mg of bacterially expressed CP (BE-CP) was purified from 1 litre of bacterial liquid culture using a Ni-NTA resin column (Qiagen). The expressed CP which migrated as a protein of approximately 23 kDa in sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis (PAGE) was identified by its strong reaction with polyclonal antibodies produced against FBNYV particles and 2-5H9 FBNYV-monoclonal in Western blots. Expressed and purified CP (SDS-PAGE 23 kDa band) was injected into a white rabbit, using seven intramuscular injections at weekly intervals. The antiserum produced was evaluated for FBNYV detection in double antibody sandwich (DAS)-enzyme-linked immunosorbent assay (ELISA), triple antibody sandwich (TAS)-ELISA, tissue blot immunoassay (TBIA), dot blot, Western blot and goat antimouse coating (GAMC)-ELISA using 13 different FBNYV monoclonal antibodies. The antiserum raised against the BE-CP gave strong FBNYV-specific TBIA reactions and very weak background reactions with non-infected tissue, similar to those produced by monoclonal antibodies. Furthermore, BE-CP polyclonal antibody reacted weakly with FBNYV-infected tissue and strongly with BE-CP in DAS-ELISA, but not with FBNYV-infected tissue in TAS-ELISA when 13 detecting monoclonal antibodies were used. In addition, BE-CP polyclonal antibody reacted strongly with BE-CP in TAS-ELISA only when 2-5H9 detecting monoclonal was used. When monoclonals were used as primary antibody and BE-CP polyclonal as detecting antibody (GAMC-ELISA), FBNYV-infected tissue gave moderate reactions with 2-5H9 and strong reactions with 3-2E9 monoclonal, whereas BE-CP gave equally strong reactions with both monoclonals. These results showed that the BE-CP polyclonal antibody is useful for the detection of FBNYV in infected tissue by TBIA and dot blot tests.
Journal of Phytopathology 12/2001; 149(9):543 - 550. · 0.79 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Murine monoclonal antibodies (MAbs) were produced for the detection of faba bean necrotic yellows virus (FBNYV), an isometric ssDNA virus belonging to a new, yet unnamed genus of plant viruses. A total of 19 FBNYV-specific MAbs were obtained from three fusion experiments and characterised by determining their immunoglobulin types and titres as well as their corresponding epitopes. At least six distinct epitopes were revealed on FBNYV particles of different virus isolates. Only two MAbs reacted with SDS-dissociated FBNYV virions in triple antibody sandwich (TAS)-ELISA and with viral capsid protein in Western blots. Almost all MAbs were more sensitive in detecting FBNYV in viruliferous aphids by TAS-ELISA than polyclonal anti-FBNYV IgG by double antibody sandwich ELISA and permitted virus detection in individual aphids even following short acquisition access feeding periods.Coat protein variation among FBNYV isolates and serological relatedness to taxonomically similar viruses was studied by determining the cross reactivity of these MAbs with several field isolates of FBNYV as well as with milk vetch dwarf (MDV), banana bunchy top (BBTV), and subterranean clover stunt (SCSV) viruses. Whereas none of the MAbs reacted with BBTV, only one reacted with SCSV, indicating that FBNYV and SCSV share a common epitope. By contrast, 16 of the 19 MAbs reacted with MDV, suggesting that FBNYV and MDV are serologically closely related and strains of the same virus. When all 19 MAbs produced were tested against a total of 107 samples of FBNYV collected during virus surveys in Egypt, Ethiopia, Jordan, Morocco and Syria, five MAbs showed differential reactions. While the majority of the samples reacted with all 19 MAbs, about 20% of the 107 FBNYV samples did not react with one and/or other of these five MAbs, permitting the differentiation of seven serotypes of FBNYV and suggesting a considerable coat protein variation in FBNYV isolates from the countries surveyed. The MDV isolate from Japan and five FBNYV samples from Ethiopia appeared to be the least closely related to typical FBNYV isolates by not reacting with three and four, respectively, of the five differentiating Mabs.
Annals of Applied Biology 03/1996; 128(2):255 - 268. · 2.18 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: One of the faba bean viruses found in West Asia and North Africa was identified as broad bean mottle virus (BBMV) by host reactions, particle morphology and size, serology, and granular, often vesiculated cytoplasmic inclusions. Detailed research on four isolates, one each from Morocco, Tunisia, Sudan and Syria, provided new information on the virus.The isolates, though indistinguishable in ELISA or gel-diffusion tests, differed slightly in host range and symptoms. Twenty-one species (12 legumes and 9 non-legumes) out of 27 tested were systemically infected, and 14 of these by all four isolates. Infection in several species was symptomless, but major legumes such as chickpea, lentil and especially pea, suffered severely from infection. All 23 genotypes of faba bean, 2 of chickpea, 4 of lentil, 11 out of 21 ofPhaseolus bean, and 16 out of 17 of pea were systemically sensitive to the virus. Twelve plant species were found to be new potential hosts and cucumber a new local-lesion test plant of the virus.BBMV particles occurred in faba bean plants in very high concentrations and seed transmission in this species (1.37%) was confirmed.An isolate from Syria was purified and two antisera were produced, one of which was used in ELISA to detect BBMV in faba bean field samples. Two hundred and three out of the 789 samples with symptoms suggestive of virus infection collected in 1985, 1986 and 1987, were found infected with BBMV: 4 out of 70 (4/70) tested samples from Egypt, 0/44 from Lebanon, 1/15 from Morocco, 46/254 from Sudan, 72/269 from Syria and 80/137 from Tunisia. This is the first report on its occurrence in Egypt, Syria and Tunisia. The virus is a potential threat to crop improvement in the region.En van de in West-Azi en Noord-Afrika in faba-boon aangetroffen virussen werd gedentificeerd als het tuinbonevlekkenvirus (broad bean mottle virus) op grond van waardplantreacties, deeltjesvorm en-grootte, serologische eigenschappen en granulaire, vaak gevacuoliseerde celinsluitsels. Verder onderzoek aan vier isolaten uit respectievelijk Marokko, Tunesi, Soedan en Syri verschafte nieuwe informatie, over het virus.De in ELISA of gel-diffusietoetsen serologisch niet te onderscheiden isolaten verschilden enigszins in waardplantenreeks en symptomen. Van 27 getoetste plantesoorten werden 21 systemisch genfecteerd (12 vlinderbloemigen, en 9 niet-vlinderbloemigen) waarvan 14 door alle vier isolaten. In vele ervan was de infectie symptoomloos, maar belangrijke als gewas geteelde vlinderbloemigen, zoals erwt, linzen en kekererwt, leden ernstig onder aantasting. Alle 23 getoetste faba-boongenotypen, beide van kekererwt, alle vier van linzen, 11 van de 21 getoetste vanPhaseolus-boon en 16 van de 17 van erwt bleken systemisch gevoelig voor het virus. Twaalf plantesoorten, bleken nieuwe potentile waardplanten en komkommer een nieuwe lokale-lesietoetsplant voor het virus te zijn.In faba-boneplanten kwam, het virus in hoge concentratie voor en overdracht met zaad (1.37%) in deze soort kon worden bevestigd.Een Syrisch isolaat werd gezuiverd en twee antisera werden bereid, waarvan n werd gebruikt voor de detectie van het virus in te velde verzamelde monsters. Van 789 in 1985 tot en met 1987 verzamelde bladmonsters, met symptomen die deden denken aan virusinfectie, bleken 203 het virus te bevatten en wel 4 van de 70 (4/70) uit Egypte, 0/44 uit Libanon, 1/15 uit Marokko, 46/254 uit Soedan, 72/269 uit Syri en 80/137 uit Tunesi. Het virus was nog niet eerder aangetoond in Egypte, Syri en Tunesi.De grote verbreiding, grote kunstmatige waardplantenreeks, overdracht met zaad, en pathogeniteit voor een aantal belangrijke vlinderbloemige gewassen maken het virus tot een potentile bedreiging van de programma's tot verbetering van de teelt van de bedoelde gewassen in het betrokken gebied.
European Journal of Plant Pathology 01/1989; 94(4):195-212. · 1.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: During a survey of faba bean viruses in West Asia and North Africa a virus was identified as broad bean stain virus (BBSV) based on host reactions, electron microscopy, physical properties and serology. An antiserum to a Syrian isolate was prepared. With this antiserum the direct double antibody sandwich ELISA (DAS-ELISA) and dot-ELISA were very sensitive in detecting BBSV in leaf extracts, ground whole seeds and germinated embryos. Sensitivity was not reduced when the two-day procedure was replaced by a one-day procedure. Using ELISA the virus was detected in 73 out of 589 faba bean samples with virus-like symptoms collected from Egypt (4 out of 70 samples tested), Lebanon (6/44), Morocco (0/7), Sudan (19/254), Syria (36/145) and Tunisia (8/69). This is the first report of BBSV infection of faba bean in Lebanon, Sudan, Syria and Tunisia. Fourteen wild legume species indigenous to Syria were susceptible to BBSV infection, with only two producing obvious symptoms. The virus was found to be seed transmitted inVicia palaestina.Tijdens een inventarisatie van virussen in veld- of tuinbonen (Vicia faba) in het Midden-Oosten en Noord-Afrika werden virusisolaten verkregen, die op grond van toetsplantreacties en fysische eigenschappen en van elektronenmicroscopische en serologische waarnemingen werden herkend als het met zaad overgaande en door snuitkevers verspreide tuinbonezaadvlekkenvirus (broad bean stain virus).Met een nieuw antiserum, gemaakt tegen een Syrisch isolaat, bleek de aantoonbaarheid van het virus in bladextracten, vermalen zaden en gekiemde embryo's erg hoog te zijn, zowel bij toepassing van DAS-ELISA als dot-ELISA. De gevoeligheid van de methode werd niet geringer wanneer de procedure werd bekort van twee dagen tot n dag.Met ELISA werd het virus aangetoond in 73 van de 589 bladmonsters van veldboon, met symptomen die deden denken aan virusinfectie, verzameld in Egypte, Libanon, Marokko, Soedan, Syri en Tunesi. Het virus werd aangetroffen in monsters uit alle genoemde landen behalve Marokko, maar het aantal uit dat land afkomstige monsters was slechts gering. Dit is de eerste maal dat het virus wordt gerapporteerd in Libanon, Soedan, Syri en Tunesi.Veertien wilde soorten vlinderbloemigen uit Syri bleken bij toetsing door inoculatie vatbaar voor infectie. Slechts twee ervan vertoonden symptomen. Het virus kan dus onzichtbaar voorkomen in de wilde vegetatie. InVicia palaestina ging het zelfs over met zaad.
European Journal of Plant Pathology 04/1987; 93(3):97-106. · 1.41 Impact Factor
-
Journal of Phytopathology 146: 347-355.
-
In: Plant Virus Disease Control (A. Hadidi, R.K. Khetarpal & H. Koganezawa, eds). APS Press, St. Paul, pp. 534-540.
