New findings of cowpea mild mottle virus in the Netherlands
The NPPO of the Netherlands recently informed the EPPO Secretariat of the recent findings of cowpea mild mottle virus (Carlavirus, CPMMV – EU A1 Quarantine pest) on its territory. CPMMV had first been found in December 2022 on potted plants of Hibiscus syriacus (EPPO RS 2023/093) and was subsequently eradicated.
Suspicious symptoms were observed again on a H. syriacus potted plant during an export inspection in July 2023. A leaf sample was taken for diagnosis. The transport of the lot of 31 H. syriacus potted plants was not put on hold and it was delivered to a third country. The presence of CPMMV in the leaf sample was confirmed in September 2023, together with three additional viruses and one viroid (Carlavirus sp., Crinivirus sp. Foveavirus sp. and Citrus viroid VI). At this nursery in the Netherlands, all 16 968 H. syriacus potted plants, which were of the same batch, were destroyed. This outbreak is considered eradicated.
At the end of August 2023 the owner of another nursery reported unknown symptoms on Hibiscus syriacus potted plant destined for the final consumer. An inspection was conducted at the end of September and the analysis of leaf samples confirmed the presence of CPMMV in November. The plants were co-infected with three additional viruses and one viroid (Carlavirus sp., Crinivirus sp., Ilarvirus sp. and Citrus viroid VI). All 111 000 H. syriacus potted plants in the nursery were put on hold and destroyed. This outbreak is considered eradicated.
It is unknown whether the symptoms were caused by CPMMV, any of the other viruses and viroid, a combination of those, or had a physiological cause. In both cases, trace-back investigations showed that the plants originated from the same Dutch nursery as in 2022. As no relevant tracing information from that nursery could be retrieved, no trace-forward activities could be initiated.
The pest status of cowpea mild mottle virus is officially declared as: Present, only in Hibiscus syriacus plants, at low prevalence.
Sources
NPPO of the Netherlands (2024-02).