Demand for tomatoes has been increasing every year as people desire more healthy food. In Korea, tomatoes are mainly grown in the Chungnam, Chunnam and Kyungnam provinces. Recently, reports of whitefly-transmitted viral diseases have increased due to newly emerging whitefly pressures caused by climate change in Korea. Specifically, in 2017, the main tomato growing areas, Buyeo and Nonsan in Chungnam, showed damage typical of viral infection; therefore, we investigated viral diseases in these areas. We collected samples with virus-like symptoms and found that not only whitefly transmitted Tomato yellow leaf curl virus (TYLCV) and Tomato chlorosis virus (ToCV) were detected but also Tomato mosaic virus (ToMV, for which no specific vector is known) and Tomato spotted wilt virus (TSWV, transmitted by thrips). The ToMV-infected samples were mostly co-infected with either TYLCV or ToCV. Mixed infections of different combinations of TYLCV, ToCV and ToMV were detected with the mixed infection of two whitefly-transmitted viruses (TYLCV and ToCV) causing the most severe symptoms. According to the CP sequence of each virus, the 100% identities were shown to be Mexico/ABG73017.1 (TYLCV), Greece/CDG34553.1 (ToCV), China/AKN79752 (TSWV), and Australia/NP078449.1 (ToMV). Based on the sequence data, we presumed that these tomato infecting viruses were transmitted through insects and seeds introduced from neighboring countries.
This work was supported by Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry and Fisheries (IPET) through Advanced Production Technology Development Program, funded by Ministry of Agriculture, Food and Rural Affairs (MAFRA) (116115-03-2-WT012).
Figures & Tables
LTypical symptoms of tomatoes infected by TYLCV, ToCV, ToMV and TSWV (BK1, BS, BK2, NS, N); TYLCV, Tomato yellow leaf curl virus; ToCV, Tomato chlorosis virus; ToMV, Tomato mosaic virus; TSWV, Tomato spotted wilt virus; BK1, Tomato yellow leaf curl virus and Tomato mosaic virus double infection; BS, Tomato chlorosis virus and Tomato mosaic virus double infection; BK2, Tomato chlorosis virus and Tomato mosaic virus double infection; NS, Tomato spotted wilt virus; N, Tomato yellow leaf curl virus and Tomato chlorosis.