Candidatus Liberibacter solanacearum (Lso) is an emerging threat to a range of crops including potato, tomato, carrot and celery and is under statutory control in the EU. Lso is vectored by insects known as psyllids. The most damaging psyllid species is Bactericera cockerelli (tomato-potato psyllid), which is associated with damage to Solanaceous crops (often referred to as “Zebra Chip” in potato) in North and Central America, New-Zealand and now South America. Both the vector and the type of Lso responsible for Zebra Chip are considered A1 quarantine pests and are not currently present in any part of Europe. In Europe, psyllids are responsible for transmitting Lso to Apiaceous crops such as carrot and can cause large economic losses. The main species responsible are Bactericera trigonica and Trioza apicalis (carrot psyllid). Whilst T. apicalis is present in the UK, it does not currently appear to be leading epidemics of the disease in carrots. Introductions of B. trigonica into the UK would be disastrous for the potato and/or carrot industry.

CaLiber research will assess the risk of haplotypes of the pathogen to become damaging epidemics should we have changes in the UK such as land use change or changes in agricultural policies.

By the end of the project our expected outcomes will be information on presence and distribution of the complex of pathogen haplotypes and how these interact with different hosts. We hope to develop tools and understanding to help manage this disease and prevent outbreaks in the UK to protect carrot and potato growing industries.