During the growing seasons of 2007 and 2008, in commercial greenhouses of tomato crops (Solanum lycopersicum L.) located in Szeged, Öcsöd, and Csongrád (southeastern regions of Hungary), unusual disease symptoms were observed, including necrotic spots in defined areas at the base of the leaflet, necrosis in the stems, and necrotic lines on the fruits surface. Affected plants appeared inside the greenhouses with a random distribution and the incidence recorded was at least 40%. These symptoms resembled those described for Tomato torrado virus (ToTV) infection in Spain (1) and Poland (3). To verify the identity of the disease, three symptomatic plants from commercial greenhouses of each geographic location were selected and analyzed by double-antibody sandwich-ELISA using polyclonal antibodies specific to Cucumber mosaic virus (CMV), Potato virus Y (PVY), Tomato mosaic virus (ToMV), Tomato spotted wilt virus (TSWV) (Loewe Biochemica, Sauerlach, Germany), and Pepino mosaic virus (PepMV) (DSMZ, Braunschweig, Germany). Total RNA was extracted and tested by reverse transcription (RT)-PCR with three pair of specific primers: one pair used to amplify the coat protein (CP) gene of PepMV (2) and the other two pairs specific to ToTV that amplify 580 bp of the polyprotein (4) and a fragment of 574 bp in the CP Vp23 (3). Nonisotopic dot-blot hybridization using a digoxygenin-labeled RNA probe complementary to the aforementioned fragment of the polyprotein was also performed. Tomato samples were negative for all the viruses tested by serological analysis and for PepMV by RT-PCR. However, all three samples were positive for ToTV by molecular hybridization and RT-PCR. RT-PCR products were purified and directly sequenced. The amplified fragments of the three Hungarian isolates, ToTV-H1, ToTV-H2, and ToTV-H3, for the polyprotein (GenBank Accession Nos. EU835496, FJ616995, and FJ616994, respectively) and the CP Vp23 (GenBank Accession Nos. FJ616996, FJ616997, and FJ616998, respectively) showed 99 to 98% nt identity with the polyprotein and the coat protein regions of ToTV from Spain and Poland (GenBank Accession Nos. DQ3888880 and EU563947, respectively). Whiteflies, commonly found in Hungarian greenhouses, have been reported to transmit ToTV (3), although the efficiency of transmission is unknown. To our knowledge, this is the first report of ToTV in Hungary. References: (1) A. Alfaro-Fernández et al. Plant Dis. 91:1060, 2007. (2) I. Pagán et al. Phytopathology 96:274, 2006. (3) H. Pospieszny et al. Plant Dis. 91:1364, 2007. (4) J. Van der Heuvel et al. Plant Virus Designated Tomato Torrado Virus. Online publication. World Intellectual Property Organization. WO/2006/085749, 2006.

Pepino mosaic virus (PepMV) has caused great concern in the greenhouse tomato industry after it was found causing a new disease in tomato in 1999. The objective of this paper is to investigate alternative hosts and compare important biological characteristics of the three PepMV strains occurring in Europe when tested under different environmental conditions. To this end we compared the infectivity and symptom development of three, well characterized isolates belonging to three different PepMV strains, EU-tom, Ch2 and US1, by inoculating them on tomato, possible alternative host plants in the family Solanaceae and selected test plants.The inoculation experiments were done in 10 countries from south to north in Europe. The importance of alternative hosts among the solanaceous crops and the usefulness of test plants in the biological characterization of PepMV isolates are discussed. Our data for the three strains tested at 10 different European locations with both international and local cultivars showed that eggplant is an alternative host of PepMV. Sweet pepper is not an important host of PepMV, but potato can be infected when the right isolate is matched with a specific cultivar. Nicotiana occidentalis 37B is a useful indicator plant for PepMV studies, since it reacts with a different symptomatology to each one of the PepMV strains.

A disease of tomato (Lycopersicon esculentum Mill.) was observed in three greenhouses in Tömörkény in southern Hungary in the autumn of 2007. Thirty percent of the plants were chlorotic and stunted and had mottled leaves with interveinal yellowing and necrosis. Similar symptoms induced by Tomato chlorosis virus (ToCV) on tomato have been reported in other countries (1,2). ToCV is a Crinivirus in the Closteroviridae family, which can cause a decline in plant vigor and reduced fruit yield. ToCV is transmitted by whiteflies (Trialeurodes vaporariorum West., T. abutilonea Hald., and Bemisia tabaci Genn.) and grafting, but cannot be transmitted mechanically. Only T. vaporariorum is known to be present and widespread in Hungary. Virus presence was confirmed by reverse transcription-PCR as described by Louro et al. (2). cDNA synthesis with ToCV specific primers (ToCV-UP 5′-TCATTAAAACTCAATGGGACCGAG-3′ (3) and ToCV-DW 5′-GCGACGTAAATTGAAACCC-3′) was successful and electron microscopy revealed ToCV-like particles. The PCR product has been sequenced (GenBank Accession No. HQ444266) and showed 97 to 99% identity to ToCV isolates in GenBank. According to the symptoms, amplified region, sequence data, and electron microscopy, the tomato samples from Tömörkény were confirmed to be infected with ToCV. The economic losses associated with ToCV were minor. To our knowledge, this is the first report on the occurrence of ToCV in Hungary. References: (1) G. P. Accotto et al. Plant Dis. 85:1208, 2001. (2) D. Louro et al. Eur. J. Plant Pathol. 106:589, 2000 (3) J. Th. J. Verhoven et al. Plant Dis. 87:872, 2003.

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