First Report of Tomato chlorosis virus in Tomato from Hungary.

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.