37 results on '"Duran-Vila, Nuria"'
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2. Is the presence of Trioza erytreae , vector of huanglongbing disease, endangering the Mediterranean citrus industry? Survey of its population density and geographical spread over the last years
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Arenas-Arenas, Francisco José, Duran-Vila, Núria, Quinto, Javier, and Hervalejo, Áurea
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- 2018
3. Citrus viruses and viroids
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Zhou, Changyong, primary, da Graça, John V., additional, Freitas-Astúa, Juliana, additional, Vidalakis, Georgios, additional, Duran-Vila, Nuria, additional, and Lavagi, Irene, additional
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- 2020
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4. Contributors
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Agustí, Manuel, primary, Aleza, Pablo, additional, Alferez, Fernando, additional, Arbona, Vicent, additional, Barry, Graham H., additional, Batuman, Ozgur, additional, Biswas, Manosh Kumar, additional, Boaretto, Rodrigo Marcelli, additional, Bowman, Kim D., additional, Cano, Liliana M., additional, Caruso, Marco, additional, Catara, Vittoria, additional, Cen, Yijing, additional, Colmenero-Flores, José M., additional, Cronje, Paul J.R., additional, Cuenca, Jose, additional, Curk, Franck, additional, da Graça, John V., additional, Deng, Xiuxin, additional, Duran-Vila, Nuria, additional, Dutt, Manjul, additional, Fabroni, Simona, additional, Feng, Shi, additional, Fernandes, Waldir, additional, Freitas-Astúa, Juliana, additional, Froelicher, Yann, additional, Gabriel, Dean, additional, Gao, Zhifeng, additional, Germanà, Maria Antonietta, additional, Gmitter, Frederick G., additional, Gómez-Cadenas, Aurelio, additional, Gottwald, Timothy R., additional, Gravena, Santin, additional, Grosser, Jude W., additional, Grout, Tim G., additional, Hyun, Jae-Wook, additional, Joubert, Johan, additional, Kadyampakeni, Davie M., additional, Kato, Masaya, additional, Kaur, Prabhjot, additional, Krueger, Robert, additional, Lavagi, Irene, additional, Li, Hongye, additional, Licciardello, Concetta, additional, Lopes, Silvio A., additional, Ma, Gang, additional, Ma, Haijie, additional, Mattos, Dirceu, additional, Morgan, Kelly T., additional, Morillon, Raphaël, additional, Oliver, Ana Quiñones, additional, Ollitrault, Patrick, additional, Palou, Lluís, additional, Primo-Millo, Eduardo, additional, Quaggio, Jose Antonio, additional, Rapisarda, Paolo, additional, Ritenour, Mark, additional, Rodrigo, María J., additional, Rokhsar, Daniel S., additional, Rouseff, Russell, additional, Russo, Giuseppe, additional, Sadka, Avi, additional, Shimizu, Tokurou, additional, Smith, Malcolm W., additional, Spreen, Thomas H., additional, Stansly, Philip A., additional, Sugiura, Minoru, additional, Tadeo, Francisco R., additional, Talon, Manuel, additional, Terol, Javier, additional, Urbaneja, Alberto, additional, Vicent, Antonio, additional, Vidalakis, Georgios, additional, Vincent, Christopher, additional, Wang, Nian, additional, Wang, Siyu, additional, Wang, Yu, additional, Wu, Fengnian, additional, Wu, Guohong Albert, additional, Wulff, Nelson A., additional, Yamamoto, Masashi, additional, Yang, Xiaoming, additional, Zacarias, Lorenzo, additional, Zansler, Marisa L., additional, Zhang, Lancui, additional, and Zhou, Changyong, additional
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- 2020
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5. Viroid infection and rootstocks affect productivity and fruit quality of the Tunisian citrus cultivar Maltaise demi sanguine
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NAJAR, Asma, HAMROUNI, Lamia, BOUHLAL, Rym, JEMMALI, Ahmed, JAMOUSSI, Bassem, and DURAN-VILA, Nuria
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- 2017
6. Citrus Exocortis Viroid
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Duran-Vila, Nuria, primary
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- 2017
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7. Geographical Distribution of Viroids in Europe
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Faggioli, Francesco, primary, Duran-Vila, Nuria, additional, Tsagris, Mina, additional, and Pallás, Vicente, additional
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- 2017
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8. List of Contributors
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Alazem, Mazen, primary, Al-Tuwariqi, Hani Z., additional, Barba, Marina, additional, Boubourakas, Iraklis N., additional, Çağlayan, Kadriye, additional, Candresse, Thierry, additional, Conejero, Vicente, additional, Dadami, Elena, additional, Dalakouras, Athanasios, additional, Daròs, José-Antonio, additional, De la Peña, Marcos, additional, Delgado, Sonia, additional, Di Serio, Francesco, additional, Dixon, Jonathan, additional, Duran-Vila, Nuria, additional, El-Dougdoug, Khaled A., additional, Elleuch, Amine, additional, Faggioli, Francesco, additional, Flores, Ricardo, additional, Fraile, Aurora, additional, Gago-Zachert, Selma, additional, Gallitelli, Donato, additional, García-Arenal, Fernando, additional, Geering, Andrew D.W., additional, Giunchedi, Luciano, additional, Gómez, Gustavo, additional, Gyamera, Ebenezer A., additional, Habili, Nuredin, additional, Hadidi, Ahmed, additional, Hallan, Vipin, additional, Hammond, Rosemarie W., additional, Hanold, Dagmar, additional, Hataya, Tatsuji, additional, Hernández, Carmen, additional, Hong, Ni, additional, Hosakawa, Munetaka, additional, Hsu, Yau-Heiu, additional, Hu, Chung-Chi, additional, Huang, Ying-Wen, additional, James, Delano, additional, Joseph, Hendry, additional, Kalantidis, Kriton, additional, Kaponi, Maria S., additional, Kim, Mikyeong, additional, Kinard, Gary R., additional, Kong, Lih L., additional, Kovalskaya, Natalia, additional, Kuhn, David N., additional, Kyriakopoulou, Panayota E., additional, Lavagi, Irene, additional, Li, Shi-Fang, additional, Lin, Na-Sheng, additional, Ling, Kai-Shu, additional, Liou, Ming-Ru, additional, Lisón, Purificación, additional, López-Carrasco, Amparo, additional, Luigi, Marta, additional, Martínez de Alba, Ángel-Emilio, additional, Mascia, Tiziana, additional, Masuta, Chikara, additional, Matoušek, Jaroslav, additional, Maurel, Marie-Christine, additional, Meekes, Ellis T.M., additional, Minoia, Sofia, additional, Navarro, Beatriz, additional, Nie, Xianzhou, additional, Owens, Robert A., additional, Pallás, Vicente, additional, Palukaitis, Peter, additional, Parakh, Dattaraj B., additional, Perreault, Jean-Pierre, additional, Podleckis, Edward V., additional, Pyle, Jesse D., additional, Randles, John W., additional, Riesner, Detlev, additional, Rodriguez, M. Judith B., additional, Roenhorst, Johanna W., additional, Roossinck, Marilyn J., additional, Rubino, Luisa, additional, Sánchez-Navarro, Jesus A., additional, Sano, Teruo, additional, Scholthof, Karen-Beth G., additional, Serra, Pedro, additional, Shimura, Hanako, additional, Singh, Rudra P., additional, Škorić, Dijana, additional, Stancanelli, Giuseppe, additional, Steger, Gerhard, additional, Taglienti, Anna, additional, Tessitori, Matilde, additional, Thanarajoo, Sathis S., additional, Tiberini, Antonio, additional, Torchetti, Enza M., additional, Tsagris, Mina, additional, Tsushima, Taro, additional, Vadamalai, Ganesan, additional, Verhoeven, Jacobus Th.J., additional, Vidalakis, Georgios, additional, Wang, Qiao-Chun, additional, Wassenegger, Michael, additional, Winter, Stephan, additional, Xu, Wen-Xing, additional, Yang, Xiuling, additional, Zhang, Yongjiang, additional, Zhang, Zhibo, additional, Zhou, Xueping, additional, and Zhu, Shuifang, additional
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- 2017
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9. Genetic variability of the coat protein gene of isolates of Citrus variegation virus from Campania (southern Italy)
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BARONE, Maria, MALFITANO, Monica, DURAN-VILA, Nuria, and ALIOTO, Daniela
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- 2009
10. VIROIDS AND VIROID DISEASES OF PLANTS
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Flores, Ricardo, primary, Di Serio, Francesco, additional, Navarro, Beatriz, additional, Duran‐Vila, Nuria, additional, and Owens, Robert A., additional
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- 2021
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11. Plant Viroids: Isolation, Characterization/Detection, and Analysis
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Owens, Robert A., primary, Sano, Teruo, additional, and Duran-Vila, Nuria, additional
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- 2012
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12. Viroids and Viroid Diseases of Plants
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Flores, Ricardo, primary, Di Serio, Francesco, additional, Navarro, Beatriz, additional, Duran-Vila, Nuria, additional, and Owens, Robert A., additional
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- 2011
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13. Genetic transformation and regeneration of mature tissues of woody fruit plants bypassing the juvenile stage
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Cervera, Magdalena, Juarez, Jose, Navarro, Antonio, Pina, Jose A., Duran-Vila, Nuria, Navarro, Luis, and Pena, Leandro
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- 1998
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14. Attachment of Agrobacterium tumefaciens B6 and A. radiobacter K84 to tomato root tips
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Penalver, Ramon, Serra, Maria T., Duran-Vila, Nuria, and Lopez, Maria M.
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Agrobacterium tumefaciens -- Analysis ,Tomatoes -- Usage ,Biological sciences - Abstract
The binding strain of Agrobacterium tumefaciens B6 to the in vitro cultured tomato root tips is greater than that of the avirulent Agrobacterium radiobacter strain K84. The latter is unable to block the attachment of the former to the tomato root tips pre-incubated with K84. This suggests that the efficiency in the biocontrol of agrocin 84-resistant strains by K84 is not related to the competition for binding to the plant root surface.
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- 1996
15. Single-strand conformation polymorphism (SSCP) analysis as a tool for viroid characterisation
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Palacio, Ana and Duran-Vila, Núria
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- 1999
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16. Enfermedades de los Cítricos. Monografía de la Sociedad Española de Fitopatología nº2
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Duran-Vila, Nuria, Moreno, Pedro, Agustí, Manuel, Bañuls Gil, Josefina, Bové, Joseph Marie, Cambra, Mariano, Duran Vila, Nuria, Garnier, Monique, Guerri, José, Legaz, Francisco, López, María Milagros, Martínez Jávega, Jose María, Moreno, Pedro, Navarro, Luís, Primo Millo, Eduardo, Serna Guirao, María Dolores, Sorribas, Francisco Javier, Timmer, Lavern W., Tuset, Juan José, Verdejo, Soledad, and Zaragoza, Salvador
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citrus, diseases, virus, fungi, bacteria - Abstract
Los cítricos sufren numerosas enfermedades causadas por agentes abióticos y bióticos, que limitan su rendimiento y a veces las posibilidades de cultivo. Las enfermedades de origen biótico incluyen las causadas por nematodos, hongos, bacterias, micoplasmas, fitoplasmas, virus y viroides, más un amplio número de enfermedades a las que se atribuye origen viral, pero cuya etiología aún no ha podido ser establecida. La mayoría de estos patógenos, en particular los virus, viroides, micoplasmas, fitoplasmas y algunas bacterias, están estrechamente asociadas al material vegetal y se dispersan con éste al propagar yemas infectadas. Algunos de ellos también se dispersan por medio de vectores, generalmente insectos. Las enfermedades de origen abiótico están normalmente ligadas a las condiciones climáticas y edafológicas en que se desarrolla el cultivo y su incidencia e importancia económica varía mucho de unas zonas a otras. A su vez, la incidencia e importancia de las enfermedades de origen biótico varía mucho de unas zonas a otras en función de las variedades cultivadas, del control sanitario que se ejerce sobre el material propagativo, las poblaciones de vectores o las condiciones ambientales. Por ello, el cuadro de enfermedades que afectan el cultivo en cada zona citrícola y la importancia relativa de las mismas es muy variable. La revisión de enfermedades de los cítricos efectuada en este libro dista de ser exhaustiva y el tratamiento que se ha dado a las distintas enfermedades se ha hecho fundamentalmente desde la óptica de las condiciones españolas y de la cuenca del Mediterráneo en general. Se han incluido capítulos en los que se describen e ilustran enfermedades que aún no se han detectado en esta zona (vg: la clorosis variegada, el huanglongbing, o las escobas de bruja de la lima), considerando su importancia económica en otras zonas citrícolas, así como la posibilidad de que en el futuro pudieran introducirse en el área mediterránea. Para prevenir esta posibilidad se ha insistido en diversos capítulos del libro sobre la importancia de los sistemas de cuarentena para evitar la introducción de nuevas enfermedades. No obstante, el tratamiento de las enfermedades ausentes de la zona mediterránea ha sido en general más breve. Este libro va dirigido fundamentalmente a investigadores no especialistas en cítricos, técnicos de explotaciones y servicios de extensión agraria, estudiantes y agricultores cualificados. Por ello, aunque en el tratamiento de las distintas enfermedades se han tenido en cuenta los avances más recientes en el conocimiento sobre cada una de ellas, se ha procurado utilizar un lenguaje sencillo y directo, reduciendo en lo posible los tecnicismos. Para facilitar la comprensión de algunos apartados por los lectores no familiarizados con la patología vegetal, se ha incluido un glosario con términos utilizados en el libro, que son poco frecuentes en el lenguaje común. La definición de estos términos se ha adaptado en general a su significado en el contexto del libro. Los editores científicos mostramos nuestro agradecimiento al profesor Fernando García-Arenal, de la Universidad Politécnica de Madrid, por su cuidadosa revisión del glosario y su ayuda para hacer unas definiciones simples y precisas. Un elemento fundamental para los objetivos divulgadores de este libro son las fotografías de síntomas. En cada caso se ha intentado seleccionar aquellos síntomas que mejor caracterizan la enfermedad, buscando un equilibrio entre la importancia de la misma en términos de incidencia y daños causados y la lógica limitación en el número de fotografías a incluir. De nuevo los editores científicos queremos expresar nuestro reconocimiento y gratitud a aquellos investigadores y técnicos que, sin ser autores de algún capítulo, han colaborado en este libro cediendo desinteresadamente fotografías de su archivo para ilustrar algunos de los síntomas descritos. En particular, a AA. Seif (Kenia), M. Koizumi (Japón), S. Garrán (Argentina), C.N. Roistacher (California, EEUU), S.M. Garnsey (Florida, EEUU) Y J. Juárez, J A, Pina, J.M. del Rivero y J. Navas-Castillo (España). Finalmente, expresamos nuestro agradecimiento a los autores de los distintos capítulos por el esfuerzo de síntesis y clarificación realizado y esperamos que éste sea de utilidad para técnicos y profesionales de la citricultura.
- Published
- 2000
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17. Phloem restriction of viroids in three citrus hosts is overcome by grafting with Etrog citron: potential involvement of a translocatable factor
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Bani-Hashemian, Seyed Mehdi, primary, Pensabene-Bellavia, Giovanni, additional, Duran-Vila, Nuria, additional, and Serra, Pedro, additional
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- 2015
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18. Gum pocket - Gummy pitting disease of trifoliate orange: Considerations about its etiology
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Duran-Vila, Nuria, Botella, Lucien, and Vernière, Christian
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Symptome ,Citrus ,Viroïde ,viruses ,Étiologie ,H20 - Maladies des plantes - Abstract
The terms "Gum pocket", "wood pitting" and "gummy pitting" have been used to describe a characteristic disorder of trifoliate orange. Affected trees show gum pockets, which develop only in the bark and wood of the trifoliate orange rootstock. This disorder has been reported in Argentina, South Africa, Australia and Italy. The association of the disease with a viroid-like RNA with the electrophoretic mobility of CVd-III was recently demonstrated. Viroid infected clementine trees grafted on trifoliate orange were monitored for the presence of gum pockets and malformations of the bud union. Trees showing gum pocket symptoms were identified in all the viroid-infected treatments as well as in some uninoculated controls. The presence of symptoms was more frequently observed (50% and 54%) on trees infected with CVd-I and CVd-IlI respectively, than in the other treatments. The symptoms appeared to be associated with trees showing a shouldered stock overgrowth. No symptoms were observed on seedlings of trifoliate orange infected with the same viroid sources. These observations suggest that gum pocket symptoms may be of physiological or stress origin. The observations made on viroid infected trees maintained for at least ten years in field trials indicate that viroid infection may act simply by enhancing the development of non specific symptoms.
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- 2003
19. CHAPTER 2 - Structure and Evolution of Viroids
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Duran-Vila, Núria, Elena, Santiago F., Daròs, José-Antonio, and Flores, Ricardo
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- 2008
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20. Microarray analysis of Etrog citron (Citrus medica L.) reveals changes in chloroplast, cell wall, peroxidase and symporter activities in response to viroid infection
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RIZZA, SERENA, primary, CONESA, ANA, additional, JUAREZ, JOSÉ, additional, CATARA, ANTONINO, additional, NAVARRO, LUIS, additional, DURAN-VILA, NURIA, additional, and ANCILLO, GEMA, additional
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- 2012
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21. The Mn-binding proteins of the photosystem II oxygen-evolving complex are decreased in date palms affected by brittle leaf disease
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Marqués, Jorge, primary, Duran-Vila, Nuria, additional, and Daròs, José-Antonio, additional
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- 2011
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22. Transcriptional response of Citrus aurantifolia to infection by Citrus tristeza virus
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Gandía, Mónica, primary, Conesa, Ana, additional, Ancillo, Gema, additional, Gadea, José, additional, Forment, Javier, additional, Pallás, Vicente, additional, Flores, Ricardo, additional, Duran-Vila, Nuria, additional, Moreno, Pedro, additional, and Guerri, José, additional
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- 2007
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23. Contributors
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Andino, Raul, Arnold, Jamie J., Barrett, John W., Bernard, Hans-Ulrich, Biebricher, Christof K., Bonhoeffer, Sebastian, Bosch, A., Bull, J.J., Buti, M., Cameron, Craig E., Daròs, José-Antonio, Davison, Andrew J., Dolan, Aidan, Domingo, Esteban, Duran-Vila, Núria, Elena, Santiago F., Escarmís, Cristina, Esteban, J.I., Flores, Richard, García-Arenal, Fernando, Gatherer, Derek, Gibbs, Adrian, Gibbs, Mark, Greene, Warner C., Hanley, Kathryn A., Hendrix, Roger W., Herrera, Mónica, Hoelzer, Karin, Holland, John J., Holmes, Edward C., Jardí, R., Martell, M., McFadden, Grant, McGeoch, Duncan J., Menéndez-Arias, Luis, Müller, Viktor, Novella, Isabel S., Ohshima, Kazusato, Parrish, Colin R., Perales, Celia, Quer, J., Rodriguez, F., Roossinck, Marilyn J., Sannjuán, R., Santiago, Mario L., Schuster, Peter, Sevilla-Reyes, Edgar E., Smidansky, Eric, Stadler, Peter F., Van Rij, Ronald, Villareal, Luis P., Wain-Hobson, Simon, Weaver, Scott C., and Wilke, C.O.
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- 2008
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24. CARACTERIZACIÓN MOLECULAR DE VARIANTES DEL VIROIDE DEL ENANISMO DEL LÚPULO (HSVd) EN EL AISLADO CUBANO PM 26-X.
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Soto, Marianela, Peralta, Esther Lilia, and Duran-Vila, Nuria
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CITRUS , *SOY isolate fiber , *GENETIC polymorphisms , *VIROID diseases of plants - Abstract
The pathogenicity of the hop stunt viroid (HSVd) variants in citrus is guided, in principle, by a series of changes and deletions located in the variable domain. These differences are evidenced by means of the molecular analysis of the present sequencies in each isolate. Starting from the Cuban isolate PM 26-X in cidro, previously characterized from the biological point of view as severe cachexia, clones were obtained and submitted to the analysis of the single strand DNA conformation polymorphism in electrophoresis in polyacrilamide gels (SSCP). Several patterns of polymorphism, which evidence that viroids are in their hosts as heterogeneous populations, were observed. A selection of the obtained clones was subjected to sequencing analysis. The obtained results were compared with the sequences previously described for other isolates. [ABSTRACT FROM AUTHOR]
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- 2004
25. COMPARACIÓN DEL LÍMITE DE DETECCIÓN DE MÉTODOS DE ANÁLISIS DE ÁCIDOS NUCLEICOS PARA EL VIROIDE DEL ENANISMO DEL LÚPULO (HSVd) EN CÍTRICOS.
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Soto, Marianela, González, Lien, Peralta, Esther Lilia, and Duran-Vila, Nuria
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VIROID diseases of plants , *GEL electrophoresis , *NUCLEIC acid hybridization , *CITRON , *CUCUMBERS - Abstract
The detection limit of sequence polyacrilamide gel electrophoresis (sPAGE), nucleic acid hybridization (NASH) and reverse transcription-polymerase chain reaction (RT-PCR) was determined for the diagnosis of the hop stunt viroid (HSVd) in citrus hosts, using citron and cucumber plants as biological amplifiers. The detection limit of sPAGE was higher (5x10-3 ) when cucumber plants were analyzed than that using citron plants (5x10-2 ); however, it was 50 times less sensitive than that of NASH (10-4 ) by comparison. The RT-PCR detection limit for cucumber host was the highest (10-6 ) of all methods analyzed. This value was higher when the RT-PCR products were detected by NASH and no with agarose gel electrophoresis instead. RT-PCR was the most sensitive method and its sensitivity was increased when it was combined with NASH. However, the presence of contaminations associated with the high sensitivity of RT-PCR is a routine diagnosis problem. On the other hand, NASH is a method with a proper sensitivity under the conditions analyzed since the detection limit was higher than that of sPAGE, although slower than that of RT-PCR. [ABSTRACT FROM AUTHOR]
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- 2007
26. IDENTIFICACIÓN DE UNA CO-VARIACIÓN EN EL DOMINIO PATOGÉNICO DEL VIROIDE DEL ENANISMO DEL LÚPULO (HSVd) INVOLUCRADA EN EL MANTENIMIENTO DE LA ESTRUCTURA SECUNDARIA DE ESTA REGIÓN.
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Soto, Marianela, González, Lien, Peralta, Esther Lilia, and Duran-Vila, Nuria
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VIROIDS , *RNA , *REVERSE transcriptase , *URACIL , *HETEROCYCLIC compounds , *HOST plants , *PLANT diseases - Abstract
Viroids are replicated in the host cell by a polymerase RNA enzyme. They exist in their hosts as quasi-species due to the high frequency of mutations it induces. Nevertheless, there are some secondary structures in their sequence that could be critical for biological functions during viroid population establishment and development in the host plant. In this paper, we analyzed the sequences and secondary structures of sequence variants of hop stunt viroid (HSVd) from citrus plants. Results evidenced that the length range of the variants was from 294 to 299 nt, and 300 nt in some cases. A conformation, that involves a two base loop of uracil, was identified in the pathogenic domain (P). The conformation did not show any variation for all the sequences analyzed, either for those pathogenic or not. For the adoption of this conformation, it is necessary the presence of a co-variation that helps to keep a determined structure within the molecule. It consists in a Guanina insertion in the 47 nucleotide of the superior chain of the domain and a Citocin complementary base in the 247 nucleotide of the inferior chain of the domain. This co-variation supports the idea that such structure in the pathogenic domain is important for some basic functions that take place during the infection (replicative process, movement in the plant, and others). [ABSTRACT FROM AUTHOR]
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- 2004
27. RESPUESTA DE DISTINTOS GENOTIPOS DE CÍTRICOS Y GÉNEROS AFINES A LA INFECCIÓN CON VIROIDES
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Seyed Mehdi, Bani Hashemian, DURAN VILA, NURIA, and Universitat Politècnica de València. Departamento de Ecosistemas Agroforestales - Departament d'Ecosistemes Agroforestals
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Cítricos ,3108 - Fitopatología ,Genotipos ,Viroides ,3108 00 ,Géneros afines - Abstract
Los especies de cítricos y géneros afines pertenecen a la familia Rutaceae. Los cítricos son huéspedes naturales de siete viroides, pero solamente Citrus exocortis viroid (CEVd) y variantes específicas de Hop stunt viroid (HSVd) causan patologías (exocortis y cachexia, respectivamente) en especies sensibles. La mayoría de los cítricos son tolerantes a las infecciones viroidales salvo algunas especies que son sensibles y manifiestan síntomas. En variedades comerciales infectadas, es frecuente encontrar los viroides como infecciones múltiples. El objetivo de este trabajo es estudiar la respuesta de distintos genotipos de cítricos a la infección con viroides. Se ha caracterizado un aislado de campo que contenía CEVd (clase A), HSVd (variante no patogénica), CBLVd (variante tipo CVd-Ia) y CDVd (variantes de tipos CVd-IIIa y CVd-IIIb), y se ha estudiado su efecto en el comportamiento de árboles de naranjo dulce 'Navelina' y clementino 'Nules', ambos injertados sobre citrange Carrizo y mantenidos en condiciones de campo durante 10 años. Los árboles de ambos cultivares alcanzaron un tamaño inferior y su cosecha fue menor que la de los controles no inoculados. Las características de los frutos también resultaron afectadas: (i) Los frutos de naranjos infectados presentaban un tamaño, índice de madurez y contenido en zumo superiores a los de los controles no infectados; (ii) los frutos de clementinos infectados presentaban un tamaño y relación diámetro/altura mayores que los de los controles no infectados; (iii) En ambos cultivares, la densidad, contenido en sólidos solubles y acidez del zumo eran inferiores a los de los controles no infectados. Los árboles infectados tenían un sistema radicular poco desarrollado y mediante histología se demostró que sus raicillas contenían menos amiloplastos que las de los controles no inoculados., Bani Hashemian, SM. (2009). RESPUESTA DE DISTINTOS GENOTIPOS DE CÍTRICOS Y GÉNEROS AFINES A LA INFECCIÓN CON VIROIDES [Tesis doctoral no publicada]. Universitat Politècnica de València. doi:10.4995/Thesis/10251/6283.
- Published
- 2015
28. Preliminary Observations on the Phytosanitary Status of the Croatian Satsuma Mandarin (Citrus unshiu Marc.) Collection
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Dijana Škorić, Silvija Černi, Katarina Hančević, Jakša Rošin, Da Graca, John, Duran-Vila, Nuria, and Moreno, Pedro
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Citrus psorosis virus ,Citrus tristeza virus ,CTV ,ELISA ,DTBIA ,biological indexing ,Life Sciences ,food and beverages ,Orange (colour) ,Biology ,biology.organism_classification ,graft-transmissible pathogens ,Chenopodium quinoa ,Citrus unshiu ,Horticulture ,Cultivar ,Orchard ,Phytosanitary certification - Abstract
Preliminary surveys of citrus field trees in Croatia showed their unsatisfactory sanitary status especially with regard to the presence of Citrus tristeza virus (CTV) even though symptoms in the field are mostly absent. The highest CTV incidence was recorded in the Satsuma mandarin (Citrus unshiu Marc), commercially the most important citrus in the country. The Satsuma collection orchard was founded in the year 2005 at the Institute for Adriatic Crops and Karst Reclamation. It encompasses 12 mandarin cultivars and 51 Satsuma clones from different sources. With the aim of assessing the phytosanitary status of Satsuma collection, biological indexing of all 12 cultivars for principal virus and virus-like diseases was performed. Seven citrus bioindicators were used ; Mexican lime, Madame Vinous and Pineapple sweet oranges, Sicilian sour orange, CRC grapefruit, Troyer and Carrizo citranges. Herbaceous hosts (white sesame, red kidney bean and Chenopodium quinoa) were also used for cool-climate pathogen detection. Serological tests (ELISA and DTBIA) were performed for CTV and Citrus psorosis virus (CPsV) directly on 18 representative clones and on Mexican lime and Madame Vinous indicators. CPsV was not detected by serology while only 2 clones were CTV-negative, both in biological and laboratory tests. Furthermore, the most severe CTV strains displaying stem-pitting and seedling yellows in grapefruit and sweet oranges were found in 4 tested clones. No biological indication of other disease presence in the collection has been found so far. Further testing of the collection Satsumas is under way, as well as the sanitation of the most important cultivars.
- Published
- 2010
29. DETECCIÓN Y CARACTERIZACIÓN AGRONÓMICA DE VIROIDES DE CÍTRICOS. IDENTIFICACIÓN Y CARACTERIZACIÓN MOLECULAR Y BIOLOGÍCA DE VARIANTES DEL VIROIDE DEL ENANISMO DE LOS CÍTRICOS CDVd
- Author
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Nubia Murcia Riaño, DURAN VILA, NURIA, and Universitat Politècnica de València. Departamento de Ecosistemas Agroforestales - Departament d'Ecosistemes Agroforestals
- Subjects
Caracterización molecular ,3103 04 ,2415 02 ,310304 - Protección de los cultivos ,3108 - Fitopatología ,Viroides ,241502 - Biología molecular de plantas ,3108 00 ,Citrus dwarfing viroid - Abstract
Los cítricos son huéspedes naturales de diferentes especies de viroides, todos pertenecientes a la familia Pospiviroidae. Estudios preliminares para detectar viroides en especies y variedades comerciales dieron resultados erráticos, excepto cuando se utilizaba la especie indicadora cidro Etrog como huésped bioamplificador. Para evitar el uso de este huésped en los ensayos de detección, se desarrolló un método basado en la hibridación northern. El protocolo desarrollado consistía en: (i) extracción de ácidos nucleicos de muestras de corteza recolectadas en diferentes épocas y/o almacenadas en distintas condiciones; (ii) separación de los RNAs en 5% PAGE o 1% agarosa y transferencia a membranas; (iii) hibridación con sondas de DNA marcadas con digoxigenina (DIG) específicas para cada viroide, detección con un anticuerpo anti-DIG conjugado con fosfatasa alcalina y revelado con un substrato quimioluminiscente (CSPD). Con este método se pueden detectar viroides en todas las especies de cítricos ensayadas. La técnica es extremadamente sensible, y acorta el tiempo necesario para la detección fiable de los viroides de cítricos conocidos hasta el momento. La aplicación de esta técnica ha permitido realizar prospecciones en árboles cultivados en distintas regiones citrícolas de Colombia, Perú y Brasil. En limas Tahití de Colombia se han identificado infecciones múltiples con HSVd y CDVd o con CEVd, HSVd y CDVd. Las muestras procedentes del Banco de Germoplasma de Palmira estaban libres de viroides, excepto una fuente de cidro Etrog que estaba infectada con CEVd y CDVd., Murcia Riaño, N. (2009). DETECCIÓN Y CARACTERIZACIÓN AGRONÓMICA DE VIROIDES DE CÍTRICOS. IDENTIFICACIÓN Y CARACTERIZACIÓN MOLECULAR Y BIOLOGÍCA DE VARIANTES DEL VIROIDE DEL ENANISMO DE LOS CÍTRICOS CDVd [Tesis doctoral no publicada]. Universitat Politècnica de València. doi:10.4995/Thesis/10251/6343.
- Published
- 2009
30. Estudios de Patogenicidad de Viroides del Género Apscaviroide y Hostuviroide en cítricos
- Author
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Pedro Serra Alfonso, DURAN VILA, NURIA, and Universitat Politècnica de València. Departamento de Biotecnología - Departament de Biotecnologia
- Subjects
Viroide ,3108 09 ,2415 00 ,310809 - Virus ,Interacción patógeno-huésped ,Cvd-v ,Patogenicidad ,Apscaviroid ,2415 - Biología molecula ,Hostuviroid - Abstract
Estudios realizados en Atalantia citroides, un género afín de los cítricos, mostraron que estaba infectada con un viroide no descrito hasta el momento. Este nuevo viroide tiene un genoma de 293-294 nucleótidos con una alta proporción de bases GC, una región central conservada que es característica de los miembros del género Apscaviroid, y también la región terminal conservada que tienen este y otros géneros de la familia Pospiviroidae. La estructura secundaria de mínima energía libre predicha para este nuevo viroide es una conformación en forma de varilla con un 68.7% de nucleótidos apareados y con una identidad de secuencia respecto a los otros viroides inferior al 90%, que es el límite convenido para separar las diferentes especies de viroides dentro de un mismo género. Los ensayos de infectividad utilizando el cidro Etrog han mostrado que este nuevo viroide produce síntomas característicos suaves. La co-inoculació de este nuevo viroide con Citrus bent leaf viroid o con Citrus dwarfing viroid, que también son miembros del género Apscaviroid, causa interacciones sinérgicas que se manifiestan induciendo síntomas muy pronunciados en las hojas y un enanismo muy marcado. Este aumento en la intensidad de síntomas no está acompañado por variaciones en la acumulación del viroide en la planta ya que su concentración se mantiene inalterada en plantas co-inoculadas. De acuerdo con estas propiedades moleculares y biológicas, así como por su capacidad por replicarse en A. citroides, este nuevo viroide que tentativamente hemos nombrado Citrus viroid V (CVd-V), ha sido propuesto como una nueva especie del género Apscaviroid.El análisis de 64 muestras provenientes de varias zonas citrícolas ha mostrado que CVd-V está presente en los Estados Unidos, España Nepal, y el Sultanato de Oman. Estos resultados indican que este viroide no ha surgido recientemente y está bastante difundido por diferentes partes del mundo. Los ensayos de transmisión a naranjo, mandarino, híb, Serra Alfonso, P. (2009). Estudios de Patogenicidad de Viroides del Género Apscaviroide y Hostuviroide en cítricos [Tesis doctoral no publicada]. Universitat Politècnica de València. doi:10.4995/Thesis/10251/6028.
- Published
- 2009
- Full Text
- View/download PDF
31. Genetic variability of Croatian Citrus tristeza virus isolates
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Gustavo Nolasco, Mladen Krajačić, Silvija Černi, Dijana Škorić, Da Graca, John, Duran-Vila, Nuria, and Moreno, Pedro
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Croatian ,Genetics ,biology ,CP gene ,CTV ,phylogenetic analysis ,SSCP ,language ,Life Sciences ,Citrus tristeza virus ,Genetic variability ,biology.organism_classification ,language.human_language ,genes p23 and p25 ,sequencing ,phylogenetic groups - Abstract
About 30 citrus field samples (Satsuma mandarins, oranges, lemons) were collected from different orchards in the Croatian coastal region (Dalmatia), including one remote island. The majority of these trees was grafted on Poncirus trifoliata and displayed no symptoms of Citrus tristeza virus (CTV) infection. However, about 50% of tested trees were found CTV infected. The genetic variability and population structure of CTV from these samples were studied by single-strand conformation polymorphism (SSCP) and sequence analysis of the cloned coat protein (p25) and RNA-binding protein (p23) genes. In the majority of isolates, CTV populations consisted of a swarm of genomic variants with the one being predominant. Surprisingly, the results of phylogenetic analysis, corroborated by a biological characterization, showed that both CP and p23 sequences clustered into five out of seven phylogenetic groups defined by Zemzami et al. (Proc. 15th IOCV, 8-12, 2002). Three of these phylogenetic groups harbor sequences of severe quick decline, seedling yellows and stem pitting isolates. It has been generally believed that some of these strains do not exist in the Mediterranean region, or if found, they are immediately eradicated. It is possible that these CTV strains were introduced into the country with the infected Satsuma material 40-20 years ago and has been continuously spreading by grafting. We also found evidence of mixed infections and recombination events in our isolates. High genetic diversity of Croatian CTV isolates and their potential for further diversification should not be overlooked in the CTV epidemiological studies of the Mediterranean basin.
- Published
- 2007
32. Pest categorisation of 'Blight and blight-like' diseases of citrus.
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Jeger M, Bragard C, Caffier D, Chatzivassiliou E, Dehnen-Schmutz K, Gilioli G, Gregoire JC, Jaques Miret JA, MacLeod A, Navajas Navarro M, Niere B, Parnell S, Potting R, Rafoss T, Rossi V, Urek G, Van Bruggen A, Van der Werf W, West J, Winter S, Catara AF, Duran-Vila N, Hollo G, Kaluski T, and Candresse T
- Abstract
The EFSA Panel on Plant Health performed a pest categorisation of 'Blight and blight-like' for the EU territory. Blight is a major disease of citrus. Similar 'blight-like' diseases are also known (e.g. declinio, declinamiento) and are addressed simultaneously with Blight in the present categorisation. The causal agent(s) remain(s) unknown and the potential role of a recently identified citrus endogenous pararetrovirus (Citrus Blight-associated pararetrovirus, CBaPRV) remains to be established. Transmissibility and ability to produce consistent (although poorly specific) symptoms have been demonstrated and a combination of indirect approaches is used, with limits, for diagnosis. There are large uncertainties on the biology of the causal agent(s) and on the epidemiology of the disease, including the transmission mechanism(s) responsible for the observed field spread. Blight has been reported from North, Central and South America, Africa and Oceania but is not known to occur in the EU. It is listed in Annex IIA of Directive 2000/29EC. It has the potential to enter, establish and spread in the EU territory. The main entry pathway (citrus plants for planting) is closed by existing legislation and entry is only possible on minor pathways (such as illegal import). Blight is a severe disease and a negative impact is expected should it be introduced in the EU, but the magnitude of this negative impact is very difficult to estimate. 'Blight and blight like' satisfies all criteria evaluated by EFSA to qualify as a Union quarantine pest. It does not meet the criterion of being present in the EU to qualify as a Union regulated non-quarantine pest (RNQP). Since the identity of the causal agent(s) of the Blight and blight-like disease(s) and the existence and efficiency of natural spread mechanism(s) remain unknown, large uncertainties affect all aspects of the present pest categorisation., (© 2018 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.)
- Published
- 2018
- Full Text
- View/download PDF
33. Pest categorisation of naturally-spreading psorosis.
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Jeger M, Bragard C, Caffier D, Dehnen-Schmutz K, Gilioli G, Gregoire JC, Jaques Miret JA, MacLeod A, Navajas Navarro M, Niere B, Parnell S, Potting R, Rafoss T, Rossi V, Urek G, Van Bruggen A, Van der Werf W, West J, Chatzivassiliou E, Winter S, Catara A, Duran-Vila N, Hollo G, and Candresse T
- Abstract
The EFSA Panel on Plant Health performed a pest categorisation of naturally-spreading psorosis of citrus for the European Union. Naturally-spreading psorosis is poorly defined, because the status of both the disease and its causal agent(s) is uncertain. However, Citrus psorosis virus (CPsV) is a well- characterised Ophiovirus that is systematically associated with the psorosis disease and therefore considered to be its causal agent. Efficient diagnostics are available for CPsV. It is present in at least three EU MS. Naturally-spreading psorosis is currently regulated by Directive 2000/29/EC, while CPsV is not explicitly mentioned in this Directive. CPsV has the potential to enter, establish and spread in the EU territory. However, the main pathway for entry is closed by the existing legislation so that entry is only possible through minor alternative pathways. Plants for planting are the major means of spread while there are uncertainties on the existence and efficiency of a natural spread mechanism. CPsV introduction and spread in the EU would have negative consequences on the EU citrus industry. Of the criteria evaluated by EFSA to qualify as a Union quarantine pest or as a Union regulated non-quarantine pest (RNQP), Naturally-spreading psorosis does not meet the criterion of being a well characterised pest or disease. As it is not explicitly mentioned in the legislation, it is unclear whether CPsV meets the criterion of being currently regulated or under official control. It meets, however, all the RNQP criteria. The key uncertainties of this categorisation concern: (1) the causal role of CPsV in the psorosis disease as well as elements of its biology and epidemiology, (2) the exact nature of the Naturally-spreading psorosis syndrome and the identity of its causal agent and, consequently, (3) whether CPsV should be considered as being covered by the current legislation., (© 2017 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.)
- Published
- 2017
- Full Text
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34. Pest categorisation of Tatter leaf virus.
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Jeger M, Bragard C, Caffier D, Dehnen-Schmutz K, Gilioli G, Gregoire JC, Jaques Miret JA, MacLeod A, Navajas Navarro M, Niere B, Parnell S, Potting R, Rafoss T, Rossi V, Urek G, Van Bruggen A, Van der Werf W, West J, Chatzivassiliou E, Winter S, Catara A, Duran-Vila N, Hollo G, and Candresse T
- Abstract
The EFSA Panel on Plant Health performed a pest categorisation of Citrus tatter leaf virus (CTLV) for the EU territory. This virus is the causal agent of tatter leaf and graft incompatibility in trifoliate orange ( Poncirus trifoliata ) and its hybrids. CTLV is now recognised as a synonym of Apple stem grooving virus (ASGV), the type Capillovirus species, for which efficient diagnostics are available. There are no known ASGV vectors. The virus is reported in citrus from many countries. In the EU, while ASGV is widely present on apple and pear, it has never been reported on citrus. Since the citrus plants for planting pathway is closed by existing legislation, the main pathway for entry is plants for planting of other host species. In the EU, the high prevalence of ASGV in non-citrus hosts, but its absence in citrus ones suggests that interspecific host transfers are rare. However, there are high uncertainties on the importance and specifics of such host change events. No limits to the establishment of ASGV are identified and spread is likely through the vegetative propagation and trade of infected hosts. Infection of sensitive citrus rootstocks leads to stunted growth and decline of the entire plant a few years after grafting. The rootstocks that are now widely used to prevent citrus tristeza decline are the most affected. Among the criteria evaluated by EFSA for an organism to qualify as a Union quarantine pest, ASGV does not meet the criterion of being absent from or under official control in the EU territory. ASGV satisfies all the criteria evaluated by EFSA to qualify as a Union regulated non-quarantine pest. The main uncertainties concern the possible unreported presence of ASGV in citrus in the EU, the existence and efficiency of interspecific host transfers and the existence of ASGV natural spread., (© 2017 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.)
- Published
- 2017
- Full Text
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35. Pest categorisation of Satsuma dwarf virus .
- Author
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Jeger M, Bragard C, Caffier D, Dehnen-Schmutz K, Gilioli G, Gregoire JC, Jaques Miret JA, MacLeod A, Navajas Navarro M, Niere B, Parnell S, Potting R, Rafoss T, Rossi V, Urek G, Van Bruggen A, Van der Werf W, West J, Chatzivassiliou E, Winter S, Catara A, Duran-Vila N, Hollo G, and Candresse T
- Abstract
The EFSA Panel on Plant Health performed a pest categorisation of Satsuma dwarf virus (SDV) for the EU territory. SDV is a well-known pathogen and the type species of the genus Sadwavirus in the family Secoviridae. SDV is now considered to include several other formerly distinct viruses which are therefore also covered in the present opinion. Citrus species and their relatives represent the main hosts of SDV and efficient diagnostic techniques are available. SDV is listed on some of its known hosts in Annex IIAI of Directive 2000/29/EC. It is transmitted by vegetative propagation of infected hosts and presumably through the soil, but the precise mechanism or vector(s) are still unknown. SDV is present in Asia and is not known to occur in the EU. Therefore, it does not meet this criterion to qualify as a Union regulated non-quarantine pest (RNPQ). Plants for planting represent the main pathway for the entry, but this pathway is closed by existing legislation for the main hosts ( Citrus , Fortunella and Poncirus ). SDV is, however, able to enter the EU on plants for plants of its unregulated rutaceous or non-rutaceous hosts. Should it be introduced, SDV has the potential to establish and subsequently spread with plants for planting and, possibly, through its poorly characterised natural spread mechanism(s). SDV is able to cause severe symptoms, quality and yield losses on a range of citrus crops. Overall, SDV meets all the criteria evaluated by EFSA to qualify as a Union quarantine pest. The main knowledge gaps and uncertainties concern (1) the potential significance of the unregulated rutaceous and non-rutaceous hosts for virus dissemination and epidemiology, (2) the origin and trade volume of the plants for planting of these host imported in the EU and (3) the efficiency of natural spread of SDV under EU conditions., (© 2017 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.)
- Published
- 2017
- Full Text
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36. Pest categorisation of Citrus tristeza virus (non-European isolates).
- Author
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Jeger M, Bragard C, Caffier D, Dehnen-Schmutz K, Gilioli G, Gregoire JC, Jaques Miret JA, MacLeod A, Navajas Navarro M, Niere B, Parnell S, Potting R, Rafoss T, Rossi V, Urek G, Van Bruggen A, Van der Werf W, West J, Chatzivassiliou E, Winter S, Catara A, Duran-Vila N, Hollo G, and Candresse T
- Abstract
The Panel on Plant Health performed a pest categorisation of non-European isolates of Citrus tristeza virus (CTV) for the EU territory. CTV is a well characterised virus for which efficient detection assays are available. It is transmitted by vegetative multiplication of infected hosts and by aphid vectors. The most efficient one, Toxoptera citricida, has limited EU presence but another one, Aphis gossypii, is broadly distributed. CTV is reported from a range of countries outside the EU and EU isolates are present in seven of the eight citrus-growing member states. Non-EU isolates are not known to occur in the EU and therefore do not meet one of the criteria for being a Union regulated non-quarantine pest. The natural host range of CTV is restricted to Citrus , Fortunella and Poncirus species. CTV non-EU isolates are listed in Annex IIAI of Directive 2000/29/EC and the main pathway for entry, plants for planting, is closed by the existing legislation. CTV isolates may therefore only enter through minor alternative pathways. They have the potential to subsequently spread through plants for planting and through the action of aphid vectors. CTV non-EU isolates are able to cause severe symptoms on a range of citrus crops that EU isolates do not induce. Overall, non-EU CTV isolates meet all the criteria evaluated by EFSA to qualify as Union quarantine pests. The main knowledge gaps and uncertainties concern (1) the status of Rutaceae species other than Citrus , Fortunella and Poncirus as natural hosts for CTV; (2) the potential undetected presence of non-EU CTV isolates in the EU and in particular the prevalence and biological properties of CTV isolates that may be present in ornamental citrus; and (3) the inability of EU CTV isolates apparently related to non-European stem pitting (SP) isolates to cause SP in sweet orange., (© 2017 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.)
- Published
- 2017
- Full Text
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37. Plant viroids: isolation, characterization/detection, and analysis.
- Author
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Owens RA, Sano T, and Duran-Vila N
- Subjects
- Electrophoresis, Polyacrylamide Gel, Plant Diseases genetics, Plant Viruses chemistry, Plant Viruses genetics, Plant Viruses isolation & purification, Plants genetics, RNA, Viral genetics, RNA, Viral isolation & purification, Reverse Transcriptase Polymerase Chain Reaction, Plant Diseases virology, Plants virology, Viroids chemistry, Viroids genetics, Viroids isolation & purification
- Abstract
When Diener discovered Potato spindle tuber viroid in 1971 (Diener, Virology 45:411-428, 1971), only a limited number of techniques were available for plant virus detection and purification. Biological assays using indicator hosts showing characteristic symptoms of infection and able to support high levels of viroid replication played a critical role in viroid detection and characterization. Polyacrylamide gel electrophoresis (PAGE) was the first molecular technique to be used for the rapid (2-3 days) identification of viroid-infected plants. Because it is the only diagnostic method that is sequence-independent, PAGE under denaturing conditions continues to play a key role in the identification of new viroids. Starting in the early 1980s, dot blot hybridization began to replace PAGE for routine viroid diagnosis. The first diagnostic protocols based on reverse transcription-polymerase chain reaction (RT-PCR) appeared approximately 10 years later, and much effort has subsequently been devoted to simplifying the sample preparation procedure and identifying group-specific primer pairs. This chapter describes four simple, easy-to-follow protocols-two involving PAGE and two others based on enzymatic amplification of viroid cDNAs-that currently play key roles in viroid discovery and characterization.
- Published
- 2012
- Full Text
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