Detection of Tobacco ringspot virus on ornamental plants in the Netherlands
The NPPO of the Netherlands recently informed the EPPO Secretariat of the finding of Tobacco ringspot virus (Nepovirus, TRSV – EPPO A2 List) on ornamental plants. Following an interception of infected Hemerocallis plants made by the USA, the Dutch NPPO carried out a survey in the premises of the exporting company concerned. In 2006-10-20, one Hemerocallis plant showing symptoms was tested and the presence of TRSV was detected. Further studies were done within the same company and showed that TRSV was present in 4 Hemerocallis varieties. All infected plants were showing symptoms and the virus was not detected in symptomless plants. Tests were done on all other plant species grown by the company and TRSV was found also in several Iris siberica and Iris ensata plants. All infected Iris siberica showed symptoms, whereas some cultivars of Iris ensata remained symptomless. Soil samples were collected from infected plots but Xiphinema americanum was not detected (X. americanum sensu stricto is a vector of TRSV which is known not to occur in Europe). Further tracing back studies showed that 3 companies had Hemerocallis plants infected by TRSV, of which 1 had also infected Iris plants. All infected plants are being destroyed. Earlier infections had been found in the Netherlands on Bacopa, Lobelia and Portulacca but were eradicated successfully (EPPO RS 2001/045).
The pest status of Tobacco ringspot virus in the Netherlands is officially declared as follows: Transient on Hemerocallis spp., Iris siberica and Iris ensata, under eradication.
Sources
NPPO of the Netherlands, 2006-12.