Update of the situation of Meloidogyne fallax in Sweden
In Sweden, the nematode Meloidogyne fallax (EPPO A2 List) was first found in 2018 in two potato (Solanum tuberosum) fields (EPPO RS 2019/038) as well as in one field that had been cropped with sugarbeet (Beta vulgaris) in the neighbouring municipalities of Kristianstad and Scania. Following these findings, official measures on movement of soil and machinery were applied, and the farmers kept their fields under black fallow in 2019. Soil samples were taken and tested in December 2019 and no second stage juvenile (J2) larvae could be detected. The farmers were allowed to grow crops that are harvested for their aboveground plant parts. Monitoring will carry on in 2020.
In 2019-2020, official monitoring for Meloidogyne chitwoodi and M. fallax was conducted, and 215 soil samples were taken according to EPPO Standard PM 9/17 National regulatory control system for Meloidogyne chitwoodi and Meloidogyne fallax. In June 2020, M. fallax was detected in one field (2 J2/100 mL soil) in the municipality of Laholm, also in Southern Sweden but on the west coast. The field was planted with peas for canning (Pisum sativum). It is suspected that the nematode was introduced either by cropping of potatoes in previous years or by soil from infested fields. Ware potatoes (Solanum tuberosum cv. Elana) were cropped in the infested field in 2019 and trace-back investigation of the seed source will be initiated. Additional monitoring surveys on the entire production site are planned after harvest of peas at the infested field, starting in the beginning of July.
The pest status of Meloidogyne fallax in Sweden is officially declared as: Present, under eradication.
Sources
NPPO of Sweden (2020-02, 2020-06).