'Candidatus Liberibacter solanacearum' detected in Trioza anthrisci specimens from the United Kingdom and Sweden
Several specimens of Trioza anthrisci (Hemiptera: Triozidae) were collected by suction traps in Northeastern Scotland (United Kingdom) and Gotland (Sweden) from 2015 to 2016, and 10 were tested for the presence of ‘Candidatus Liberibacter solanacearum’ (potato haplotypes are listed in EPPO A1 List). Five out of 6 specimens from the United Kingdom and 2 out of 4 specimens from Sweden tested positive (real-time PCR) for ‘Ca. L. solanacearum’ haplotype C. This is the first time that this bacterium is detected in T. anthrisci, which can be considered as a new potential vector. This psyllid has been reported in Scandinavia, Western and Central Europe, Turkey and Russia (Altai); and in the United Kingdom, its host plants include: Angelica sylvestris, Anthriscus sylvestris, Chaerophyllum hirsutum, Heracleum sphondylium (all Apiaceae).
In Sweden, ‘Ca. L. solanacearum’ (haplotype C) had already been detected in association with a disease on carrots (Daucus carota) (EPPO RS 2012/119, 2016/194). However, in the United Kingdom and prior to this finding, ‘Ca. L. solanacearum’ had never been reported in crops, weeds or psyllids, but only in parsley (Petroselinum crispum) seeds collected from local shops (EPPO RS 2017/129).
Sources
Sjölund MJ, Clark M, Carnegie M, Greenslade AFC, Ouvrard D, Highet F, Sigvald R, Bell JR, Arnsdorf YM, Cairns R, Kenyon DM (2017) First report of 'Candidatus Liberibacter solanacearum' in the United Kingdom in the psyllid Trioza anthrisci. New Disease Reports 36(4). http://dx.doi.org/10.5197/j.2044-0588.2017.036.004