First record of watermelon crinkle leaf-associated virus 1 (WCLaV-1) and WCLaV-2 in Slovenia
Watermelon crinkle leaf-associated virus 1(Coguvirus citrulli, WCLaV-1 – EPPO Alert List) and watermelon crinkle leaf-associated virus 2 (Coguvirus henanense, WCLaV-2 – EPPO Alert List) are first reported from Slovenia. In July 2024, a pooled leaf sample was collected from several plants of three watermelon cultivars (Citrullus lanatus) grown in an open field (approx. 5000 m2) in Dombrava (Gorizia region) in western Slovenia. Plants showed leaf mosaic, wilting and necrosis. The disease incidence was estimated at 10%. The sample tested positive by RT-PCR for both WCLaV-1 and WCLaV-2.
In addition, five watermelon seed samples from commercial seed lots were tested as well as seedlings obtained from those seed lots, and both viruses were found in all seeds and seedlings tested. Retrospective analyses of HTS data showed that WCLaV-1 and WCLaV-2 were present in some watermelon seeds in 2018 and 2019 (but not in other cucurbit seeds).
This is the first record of WCLaV-1 in the EPPO region and the second of WCLaV-2 (EPPO RS 2025-098).
The situation of WCLaV-1 and WCLaV-2 in Slovenia can be described as: Present, restricted distribution (one field).
Sources
Vučurović A, Bajde I, Brodarič J, Pecman A, Kogej-Zwitter Z, Bukvič V, Jakoš N, Kutnjak D, Rot M, Mehle N (2025) First report of watermelon crinkle leaf-associated virus 1 (WCLaV-1) and WCLaV-2 in watermelon in Slovenia. Plant Disease (early view) https://doi.org/10.1094/PDIS-02-25-0251-PDN