Multi-Thread Hydrodynamic Modeling of a Solar Flare

Past hydrodynamic simulations have been able to reproduce the high temperatures and densities characteristic of solar flares. These simulations, however, have not been able to account for the slow decay of the observed flare emission or the absence of blueshifts in high spectral resolution line profiles. Recent work has suggested that modeling a flare as an sequence of independently heated threads instead of as a single loop may resolve the discrepancies between the simulations and observations. In this paper we present a method for computing multi-thread, time-dependent hydrodynamic simulations of solar flares and apply it to observations of the Masuda flare of 1992 January 13. We show that it is possible to reproduce the temporal evolution of high temperature thermal flare plasma observed with the instruments on the \textit{GOES} and \textit{Yohkoh} satellites. The results from these simulations suggest that the heating time-scale for a individual thread is on the order of 200 s. Significantly shorter heating time scales (20 s) lead to very high temperatures and are inconsistent with the emission observed by \textit{Yohkoh}.Comment: Submitted to Ap

Efectos de la maduración y el procesamiento sobre la calidad nutricional y sensorial de las aceitunas de mesa Itrana

In the present study, we evaluated the nutritional and sensory characteristics of table olives of the Italian doubleaptitude olive cultivar (Olea europaea L. cv. Itrana) processed as green (Oliva bianca di Itri) and black (Oliva di Gaeta) table olives with modified Greek methods of preparation. One method provides an initial step of immersion in water to stimulate the growth of specific microflora which contributes to the debittering of the fruits. After 15-45 days, salt is added to the liquid in quantities not exceeding 8 kg per 100 kg of fresh olives. Another method entails the immersion of fruits directly in brine utilizing double-salting (half the amount of NaCl was added immediately and the remaining part after 15 days). All the information derived from chemico-physical, nutritional and sensory data have separated the samples into four groups according to techno-processings, ripening stage and storage. Double-salting is the method which assures the best results.En el presente estudio se evalúan las características nutricionales y sensoriales de la variedad Itrana de aceituna (Olea europaea L.) de doble uso, elaborada en verde (Oliva Bianca di Itri) y en negro (Oliva di Gaeta), utilizando métodos griegos modificados al efecto. Un método consiste en una etapa inicial de inmersión en agua para favorecer el crecimiento de una flora específica que contribuye al endulzado de los frutos. Después de 15-45 días se añade sal a la solución en una cantidad que no exceda 8 kg por 100 g de fruto fresco. Otro procedimiento consiste en colocar directamente las aceitunas en salmuera utilizando un sistema de adición de la sal en dos etapas (la mitad de la sal se añade inmediatamente y el resto a los 15 días). Toda la información derivada de los análisis fisico-químicos, nutricionales y sensoriales ha permitido la separación de las muestras en cuatro grupos según la tecnología de elaboración, el estado de madurez y el almacenamiento. El proceso de adición de sal en dos etapas (“double salting”) fue el procedimiento que dio mejores resultados

Helium Recovery in the LHC Cryogenic System following Magnet Resistive Transitions

A resistive transition (quench) of the Large Hadron Collider magnets provokes the expulsion of helium from the magnet cryostats to the helium recovery system. A high-volume, vacuum-insulated recovery line connected to several uninsulated medium-pressure gas storage tanks, forms the main constituents of the system. Besides a dedicated hardware configuration, helium recovery also implies specific procedures that should follow a quench, in order to conserve the discharged helium and possibly make use of its refrigeration capability. The amount of energy transferred after a quench from the magnets to the helium leaving the cold mass has been estimated on the basis of experimental data. Based on these data, the helium thermodynamic state in the recovery system is calculated using a lumped parameter approach. The LHC magnet quenches are classified ina parametric way from their cryogenic consequences and procedures that should follow the quench are proposed

Sex and gender optometry: from retinal design to stereopsis

Scientific research in optometry aims to increase the ability to predict optical effects induced by lens fitting, allowing us to understand how geometrical concepts and physical phenomena translate into perceptual responses. It is possible, for instance, to investigate how differential perspective affects three-dimensional perception, indeed the ocular parallax error, that occurs as the eyes are separated horizontally by a certain distance (DAV), allows for the depth interval between two object points to be appreciated and transferred to the retina. In a study conducted at the University of Turin, the DAVs measured on a group of students were compared with the students’ stereo acuity values, with the aim of highlighting whether female subjects, whose DAVs are smaller than those of men, actually have less sense of depth. The measurement protocol and the results obtained will be explained. The research perspective is the parameterization of optometric tests to take into account differences due to gender, in order to detect any abnormalities more accurately

Identification and characterization of citrus concave gum-associated virus infecting citrus and apple trees by serological, molecular and high-throughput sequencing approaches

Citrus concave gum-associated virus (CCGaV) is a negative-stranded RNA virus, first reported a few years ago in citrus trees from Italy. It has been reported in apple trees in the USA and in Brazil, suggesting a wider host range and geographic distribution. Here, an anti-CCGaV polyclonal antiserum to specifically detect the virus has been developed and used in a standard double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) that has been validated as a sensitive and reliable method to detect this virus both in citrus and apple trees. In contrast, when the same antiserum was used in direct tissue-blot immunoassay, CCGaV was efficiently detected in citrus but not in apple. Using this antiserum, the first apple trees infected by CCGaV were identified in Italy and the presence of CCGaV in several apple cultivars in southern Italy was confirmed by field surveys. High-throughput sequencing (HTS) allowed for the assembling of the complete genome of one CCGaV Italian apple isolate (CE-c3). Phylogenetic analysis of Italian CCGaV isolates from apple and citrus and those available in the database showed close relationships between the isolates from the same genus (Citrus or Malus), regardless their geographical origin. This finding was further confirmed by the identification of amino acid signatures specific of isolates infecting citrus or apple hosts. Analysis of HTS reads also revealed that the CE-c3 Italian apple tree, besides CCGaV, was simultaneously infected by several viruses and one viroid, including apple rubbery wood virus 2 which is reported for the first time in Italy. The complete or almost complete genomic sequences of the coinfecting agents were determined

Towards dissecting the structural determinant of Peach latent mosaic viroid inducing mosaic symptoms

Most isolates of Peach latent mosaic viroid (PLMVd) do not incite foliar symptoms, but a few number of isolates cause peach mosaic (PM) or peach calico (PC), an extreme albino phenotype. The PC determinant has been previously mapped at an insertion of 12-13 nt folding into a hairpin capped by a U-rich loop but the PM determinant, which is not associated with a specific insertion, remains unidentified and could reside in one or more domains of the branched conformation proposed for PLMVd. To tackle this problem we have selected for further dissection one variant (GDS6), recovered from a typical PM isolate (GDS), which is very infectious and elicits consistently a characteristic PM. We have initially focused on G337, a position that appears associated with PM in multiple alignments that include GDS6 and other PM-inducing and latent variants. To determine the role of G337 in infectivity and symptoms, GF-305 peach seedlings were inoculated with in vitro transcripts of recombinant plasmids containing dimeric tandem inserts of PLMVd-cDNAs with all possible changes at this position introduced by site-directed mutagenesis. Deletion of G337 abolished infectivity, while substitutions by A, C or U incited, in most inoculated plants, PM symptoms. Cloning and sequencing showed that the A substitution at position 337 was preserved in the progeny or reverted to G, while C or U substitutions at this position were not stable and reverted to A or G in the progenies. Extending this approach to additional nucleotides of loop A, or of other PLMVd domains, may provide hints in identifying the determinant of PM. Keywords: Viroids, Pathogenesis, Peach diseas

Pome fruit viruses in Bosnia and Herzegovina

During autumn 2005 and summer 2006, field surveys were carried out to assess the sanitary status of pome fruit trees in Bosnia and Herzegovina. Inspections were done in the main pome fruit growing areas including 10 orchards, 2 nurseries and one varietal collection. A total of 65 apple and 50 pear cultivars were tested by biological indexing for the presence of Apple chlorotic leaf spot virus (ACLSV), Apple stem pitting virus (ASPV), Apple stem grooving virus (ASGV) and Apple mosaic virus (ApMV). The average infection level was 81%. Both species showed a similar infection rate (83% for apple and 78% for pear). The most frequent viruses of apple were ACLSV (72%) and ASPV (69%), and of pear ASGV (69%) and ACLSV (64%). The same samples were also tested by ELISA, with a lower virus detection rate compared to the biological indexing. Multiplex RT-PCR results of 20 randomly selected apple cultivars were in line with biological indexing. Results of our surveys report for the first time th e presence of ACLSV, ASPV, ASGV and ApMV on pome fruits in Bosnia and Herzegovina.Keywords: Malus, biological indexing, ELISA, multiplex RT-PCR, sanitary statu

Viroid diseases in pome and stone fruit trees and Koch s postulates: a critical assessment

[EN] Composed of a naked circular non-protein-coding genomic RNA, counting only a few hundred nucleotides, viroids¿the smallest infectious agents known so far¿are able to replicate and move systemically in herbaceous and woody host plants, which concomitantly may develop specific diseases or remain symptomless. Several viroids have been reported to naturally infect pome and stone fruit trees, showing symptoms on leaves, fruits and/or bark. However, Koch¿s postulates required for establishing on firm grounds the viroid etiology of these diseases, have not been met in all instances. Here, pome and stone fruit tree diseases, conclusively proven to be caused by viroids, are reviewed, and the need to pay closer attention to fulfilling Koch¿s postulates is emphasized. View Full-TextThis project has received funding from the European Union's Horizon 2020 Research and Innovation Scientific Exchange Program under the Marie Sklodowska-Curie grant agreement No. 734736. This publication reflects only the authors' view. The Agency is not responsible for any use that may be made of the information it contains.Di Serio, F.; Ambros Palaguerri, S.; Sano, T.; Flores Pedauye, R.; Navarro, B. (2018). Viroid diseases in pome and stone fruit trees and Koch s postulates: a critical assessment. Viruses. 10(11). https://doi.org/10.3390/v101106121011Diener, T. O. (1971). Potato spindle tuber «virus». Virology, 45(2), 411-428. doi:10.1016/0042-6822(71)90342-4Flores, R., Minoia, S., Carbonell, A., Gisel, A., Delgado, S., López-Carrasco, A., … Di Serio, F. (2015). Viroids, the simplest RNA replicons: How they manipulate their hosts for being propagated and how their hosts react for containing the infection. Virus Research, 209, 136-145. doi:10.1016/j.virusres.2015.02.027López-Carrasco, A., & Flores, R. (2016). Dissecting the secondary structure of the circular RNA of a nuclear viroid in vivo: A «naked» rod-like conformation similar but not identical to that observed in vitro. RNA Biology, 14(8), 1046-1054. doi:10.1080/15476286.2016.1223005López-Carrasco, A., & Flores, R. (2017). The predominant circular form of avocado sunblotch viroid accumulates in planta as a free RNA adopting a rod-shaped secondary structure unprotected by tightly bound host proteins. Journal of General Virology, 98(7), 1913-1922. doi:10.1099/jgv.0.000846Flores, R., Hernández, C., Alba, A. E. M. de, Daròs, J.-A., & Serio, F. D. (2005). Viroids and Viroid-Host Interactions. Annual Review of Phytopathology, 43(1), 117-139. doi:10.1146/annurev.phyto.43.040204.140243Di Serio, F., Flores, R., Verhoeven, J. T. J., Li, S.-F., Pallás, V., Randles, J. W., … Owens, R. A. (2014). Current status of viroid taxonomy. 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Chrysanthemum chlorotic mottle viroid: Unusual structural properties of a subgroup of self-cleaving viroids with hammerhead ribozymes. Proceedings of the National Academy of Sciences, 94(21), 11262-11267. doi:10.1073/pnas.94.21.11262De la Pena, M., Navarro, B., & Flores, R. (1999). Mapping the molecular determinant of pathogenicity in a hammerhead viroid: A tetraloop within the in vivo branched RNA conformation. Proceedings of the National Academy of Sciences, 96(17), 9960-9965. doi:10.1073/pnas.96.17.9960Bellamy, A. R., & Ralph, R. K. (1968). [104] Recovery and purification of nucleic acids by means of cetyltrimethylammonium bromide. Nucleic Acids, Part B, 156-160. doi:10.1016/0076-6879(67)12125-3Codoñer, F. M., Darós, J.-A., Solé, R. V., & Elena, S. F. (2006). The Fittest versus the Flattest: Experimental Confirmation of the Quasispecies Effect with Subviral Pathogens. PLoS Pathogens, 2(12), e136. doi:10.1371/journal.ppat.0020136Hashimoto, J., & Koganezawa, H. (1987). Nucleotide sequence and secondary structure of apple scar skin viroid. Nucleic Acids Research, 15(17), 7045-7052. doi:10.1093/nar/15.17.7045Zhu, S. F., Hadidi, A., & Hammond, R. W. (1998). AGROINFECTION OF PEAR AND APPLE WITH DAPPLE APPLE VIROID RESULTS IN SYSTEMIC INFECTION. Acta Horticulturae, (472), 613-616. doi:10.17660/actahortic.1998.472.81OSAKI, H., KUDO, A., & OHTSU, Y. (1996). Japanese Pear Fruit Dimple Disease Caused by Apple Scar Skin Viroid (ASSVd). Japanese Journal of Phytopathology, 62(4), 379-385. doi:10.3186/jjphytopath.62.379Ito, T., & Yoshida, K. (1998). REPRODUCTION OF APPLE FRUIT CRINKLE DISEASE SYMPTOMS BY APPLE FRUIT CRINKLE VIROID. Acta Horticulturae, (472), 587-594. doi:10.17660/actahortic.1998.472.78Hadidi, A., & Yang, X. (1990). Detection of pome fruit viroids by enzymatic cDNA amplification. Journal of Virological Methods, 30(3), 261-269. doi:10.1016/0166-0934(90)90068-qKyriakopoulou, P. E., & Hadidi, A. (1998). NATURAL INFECTION OF WILD AND CULTIVATED PEARS WITH APPLE SCAR SKIN VIROID IN GREECE. Acta Horticulturae, (472), 617-626. doi:10.17660/actahortic.1998.472.82Ambros, S., Desvignes, J. C., Llacer, G., & Flores, R. (1995). Pear blister canker viroid: sequence variability and causal role in pear blister canker disease. Journal of General Virology, 76(10), 2625-2629. doi:10.1099/0022-1317-76-10-2625Sano, T., Hataya, T., Terai, Y., & Shikata, E. (1989). Hop Stunt Viroid Strains from Dapple Fruit Disease of Plum and Peach in Japan. Journal of General Virology, 70(6), 1311-1319. doi:10.1099/0022-1317-70-6-1311Flores, R., Hernández, C., Desvignes, J. C., & Llácer, G. (1990). Some properties of the viroid inducing peach latent mosaic disease. Research in Virology, 141(1), 109-118. doi:10.1016/0923-2516(90)90060-vMalfitano, M., Di Serio, F., Covelli, L., Ragozzino, A., Hernández, C., & Flores, R. (2003). Peach latent mosaic viroid variants inducing peach calico (extreme chlorosis) contain a characteristic insertion that is responsible for this symptomatology. Virology, 313(2), 492-501. doi:10.1016/s0042-6822(03)00315-5Puchta, H., Luckinger, R., Yang, X., Hadidi, A., & S�nger, H. L. (1990). Nucleotide sequence and secondary structure of apple scar skin viroid (ASSVd) from China. Plant Molecular Biology, 14(6), 1065-1067. doi:10.1007/bf00019406KOGANEZAWA, H. (1985). Transmission to apple seedlings of a low molecular weight RNA extracted from apple scar skin diseased trees. Japanese Journal of Phytopathology, 51(2), 176-182. doi:10.3186/jjphytopath.51.176Koganezawa, H. (1986). FURTHER EVIDENCE FOR VIROID ETIOLOGY OF APPLE SCAR SKIN AND DAPPLE APPLE DISEASES. Acta Horticulturae, (193), 29-34. doi:10.17660/actahortic.1986.193.2Yamaguch, A., & Yanase, H. (1976). POSSIBLE RELATIONSHIP BETWEEN THE CAUSAL AGENT OF DAPPLE APPLE AND SCAR SKIN. Acta Horticulturae, (67), 249-254. doi:10.17660/actahortic.1976.67.31Desvignes, J. C., Grasseau, N., Boyé, R., Cornaggia, D., Aparicio, F., Di Serio, F., & Flores, R. (1999). Biological Properties of Apple Scar Skin Viroid: Isolates, Host Range, Different Sensitivity of Apple Cultivars, Elimination, and Natural Transmission. Plant Disease, 83(8), 768-772. doi:10.1094/pdis.1999.83.8.768Walia, Y., Dhir, S., Bhadoria, S., Hallan, V., & Zaidi, A. A. (2011). Molecular characterization of Apple scar skin viroid from Himalayan wild cherry. Forest Pathology, 42(1), 84-87. doi:10.1111/j.1439-0329.2011.00723.xDi Serio, F., Aparicio, F., Alioto, D., Ragozzino, A., & Flores, R. (1996). Identification and molecular properties of a 306 nucleotide viroid associated with apple dimple fruit disease. Journal of General Virology, 77(11), 2833-2837. doi:10.1099/0022-1317-77-11-2833Di Serio, F., Giunchedi, L., Alioto, D., Ragozzino, A., & Flores, R. (1998). IDENTIFICATION OF APPLE DIMPLE FRUIT VIROID IN DIFFERENT COMMERCIAL VARIETIES OF APPLE GROWN IN ITALY. Acta Horticulturae, (472), 595-602. doi:10.17660/actahortic.1998.472.79Roumi, V., Gazel, M., & Caglayan, K. (2017). First report of Apple dimple fruit viroid in apple trees in Iran. New Disease Reports, 35, 3. doi:10.5197/j.2044-0588.2017.035.003He, Y.-H., Isono, S., Kawaguchi-Ito, Y., Taneda, A., Kondo, K., Iijima, A., … Sano, T. (2010). Characterization of a new Apple dimple fruit viroid variant that causes yellow dimple fruit formation in ‘Fuji’ apple trees. Journal of General Plant Pathology, 76(5), 324-330. doi:10.1007/s10327-010-0258-xChiumenti, M., Torchetti, E. M., Di Serio, F., & Minafra, A. (2014). Identification and characterization of a viroid resembling apple dimple fruit viroid in fig (Ficus carica L.) by next generation sequencing of small RNAs. Virus Research, 188, 54-59. doi:10.1016/j.virusres.2014.03.026ITO, T., KANEMATSU, S., KOGANEZAWA, H., TSUCHIZAKI, T., & YOSHIDA, K. (1993). Detection of a Viroid Associated with Apple Fruit Crinkle Disease. Japanese Journal of Phytopathology, 59(5), 520-527. doi:10.3186/jjphytopath.59.520Sano, T., Yoshida, H., Goshono, M., Monma, T., Kawasaki, H., & Ishizaki, K. (2004). Characterization of a new viroid strain from hops: evidence for viroid speciation by isolation in different host species. Journal of General Plant Pathology, 70(3), 181-187. doi:10.1007/s10327-004-0105-zNakaune, R., & Nakano, M. (2008). Identification of a new Apscaviroid from Japanese persimmon. Archives of Virology, 153(5), 969-972. doi:10.1007/s00705-008-0073-2Hernandez, C., Elena, S. F., Moya, A., & Flores, R. (1992). Pear Blister Canker Viroid is a Member of the Apple Scar Skin Subgroup (apscaviroids) and also has Sequence Homology with Viroids from other Subgroups. Journal of General Virology, 73(10), 2503-2507. doi:10.1099/0022-1317-73-10-2503Lemoine, J. (1986). PROBLEMS REGARDING THE DETECTION OF GRAFT TRANSMITTED PEAR CANKER. Acta Horticulturae, (193), 251-260. doi:10.17660/actahortic.1986.193.43Ambrós, S., Llácer, G., Desvignes, J. C., & Flores, R. (1995). PEACH LATENT MOSAIC AND PEAR BLISTER CANKER VIROIDS: DETECTION BY MOLECULAR HYBRIDIZATION AND RELATIONSHIPS WITH SPECIFIC MALADIES AFFECTING PEACH AND PEAR TREES. Acta Horticulturae, (386), 515-521. doi:10.17660/actahortic.1995.386.74Flores, R., Hernandez, C., Llacer, G., & Desvignes, J. C. (1991). Identification of a new viroid as the putative causal agent of pear blister canker disease. Journal of General Virology, 72(6), 1199-1204. doi:10.1099/0022-1317-72-6-1199Desvignes, J. C., Cornaggia, D., Grasseau, N., Ambrós, S., & Flores, R. (1999). Pear Blister Canker Viroid: Host Range and Improved Bioassay with Two New Pear Indicators, Fieud 37 and Fieud 110. Plant Disease, 83(5), 419-422. doi:10.1094/pdis.1999.83.5.419SASAKI, M., & SHIKATA, E. (1977). On Some Properties of Hop Stunt Disease Agent, a Viroid. Proceedings of the Japan Academy. Ser. B: Physical and Biological Sciences, 53(3), 109-112. doi:10.2183/pjab.53.109Ohno, T., Takamatsu, N., Meshi, T., & Okada, Y. (1983). Hop stunt viroid: molecular cloning and nucleotide sequence of the complete cDNA copy. Nucleic Acids Research, 11(18), 6185-6197. doi:10.1093/nar/11.18.6185Kofalvi, S. A., Pall√°s, V., Marcos, J. F., Candresse, T., & Ca√±izares, M. C. (1997). Hop stunt viroid (HSVd) sequence variants from Prunus species: evidence for recombination between HSVd isolates. Journal of General Virology, 78(12), 3177-3186. doi:10.1099/0022-1317-78-12-3177Amari, K., Gomez, G., Myrta, A., Di Terlizzi, B., & Pallás, V. (2001). The molecular characterization of 16 new sequence variants of Hop stunt viroid reveals the existence of invariable regions and a conserved hammerhead-like structure on the viroid molecule The sequences described in this work have been deposited in the EMBL database and received accession numbers AJ297825 to AJ297840. Journal of General Virology, 82(4), 953-962. doi:10.1099/0022-1317-82-4-953SANO, T., HATAYA, T., TERAI, Y., & SHIKATA, E. (1986). Association of a viroid-like RNA from plum dapple disease occurring in Japan. Proceedings of the Japan Academy. Ser. B: Physical and Biological Sciences, 62(3), 98-101. doi:10.2183/pjab.62.98Hernandez, C., & Flores, R. (1992). Plus and minus RNAs of peach latent mosaic viroid self-cleave in vitro via hammerhead structures. Proceedings of the National Academy of Sciences, 89(9), 3711-3715. doi:10.1073/pnas.89.9.3711Ambros, S. (1998). In vitro and in vivo self-cleavage of a viroid RNA with a mutation in the hammerhead catalytic pocket. Nucleic Acids Research, 26(8), 1877-1883. doi:10.1093/nar/26.8.1877Ambrós, S., Hernández, C., & Flores, R. (1999). Rapid generation of genetic heterogeneity in progenies from individual cDNA clones of peach latent mosaic viroid in its natural host The data reported in this paper are in the EMBL nucleotide sequence database and assigned the accession nos AJ241818–AJ241850. Journal of General Virology, 80(8), 2239-2252. doi:10.1099/0022-1317-80-8-2239Fekih Hassen, I., Massart, S., Motard, J., Roussel, S., Parisi, O., Kummert, J., … Jijakli, M. H. (2007). Molecular features of new Peach Latent Mosaic Viroid variants suggest that recombination may have contributed to the evolution of this infectious RNA. Virology, 360(1), 50-57. doi:10.1016/j.virol.2006.10.021DUBÉ, A., BOLDUC, F., BISAILLON, M., & PERREAULT, J.-P. (2011). Mapping studies of the Peach latent mosaic viroid reveal novel structural features. 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Identification, full-length genome sequencing, and field survey of citrus vein enation virus in Italy

Citrus vein enation virus (CVEV) was described in Spain and then it has been reported in several citrus growing areas of Asia, America and Australia. Here, the occurrence of CVEV in Italy has been documented for the first time. The full genome sequence of a CVEV Italian isolate (14Q) was determined by high-throughput sequencing and the presence of the virus was confirmed by RT-PCR and graft-transmission to indicator plants, from which the virus was recovered six-months post-inoculation. Phylogenetic analysis based on the full-length genome of CVEV isolates from different countries showed that they are phylogenetically related to each other based on their geographic origin, rather than on their host and that the Italian isolate is more closely related to the Spanish isolate than to the other ones. A field survey revealed the presence of CVEV in some areas of Campania region (southern Italy), prevalently infecting lemon trees. In the frame of this survey, kumquat was identified for the first time as a host of CVEV. No symptoms were observed in the field so far. The infection of asymptomatic hosts and the transmission by aphid species present in Italy increase the risk that the virus could further spread