Physical properties and host range of tomato yellow leaf curl virus isolated from tomato in Kyoto Prefecture

Yellow leaf curl disease of tomato caused by tomato yellow leaf curl virus (TYLCV: a begomovirus) results in severe damage. In general, the virus is transmitted by the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) and difficult to inoculate mechanically to plants. As mechanical inoculation has numerous practical uses, e.g., screening for resistant tomato varieties, we developed a method using a toothbrush to inoculate susceptible tomato plants with TYLCV. In this study, we investigated the physical properties and host range of TYLCV-Kumiyama isolated in Kyoto Prefecture, and the following results were obtained: thermal inactivation point of 75°C–78°C for 10 min, dilution end point of 10–6, and longevity in vitro of 6 days at 25°C. Nine species belonging to four families were infected with the virus. The symptoms consisted primarily of yellowing or vein yellowing.