Relevant domestic and international literature on grapevine viruses has been collected and reviewed, and a preliminary database has been established covering the characteristics, transmission pathways, and epidemiological information of grapevine viruses commonly found in Taiwan. Epidemiological information on six major grapevine viruses has also been compiled.

In addition, surveys were conducted to investigate virus infections in grafted and cutting-propagated grapevine seedlings and commonly used rootstocks at Neiwan in Miaoli, and Xinshe in Taichung. A total of 50 grapevine seedlings, mainly‘Kyoho’, and 8 plants representing four rootstock types were collected to assess virus infection in seedlings from different sources and rootstocks. The results showed that Grapevine geminivirus A (GGVA) and Grapevine fleck virus (GFkV) were among the most prevalent viruses in the surveyed fields and frequently occurred as mixed infections. Virus infections were detected in both seedlings from different sources and rootstocks（Fig. 1、Fig. 2）, indicating that virus-infected propagation materials may represent an important pathway for the transmission and spread of grapevine viruses.

Further surveys and comparative monitoring across additional production areas will be conducted to clarify the major sources of grapevine virus transmission and to assess associated epidemiological risks.

▲Figure 1. Virus-carrying status of grafted and cutting-propagated grapevine seedlings in Neiwan and Xinshe.

▲Figure 2. Survey and assessment of the virus-carrying status of commonly used rootstocks in Neiwan, Miaoli.