show Abstracthide AbstractCandidatus Liberibacter solanacearum (Lso) is a bacterium which causes zebra chip disease in potato. Lso exists in different variants (called haplotypes). Different variants can also lead to significant losses in other crops including tomato, carrot, and celery in some parts of the world. Lso is not currently causing widespread damage in the UK despite the bacterium being present here. Essential to understanding the spread of Lso is understanding the insects that carry it. The disease is only transmitted from plant to plant by sap-feeding insects called psyllids. These insects are highly specific, typically feeding on just one or a few host plant species. This means that for disease to occur both the plant-specific psyllid, and a suitable Lso haplotype need to be present. Sequencing of psyllid vectors is an objective of the CALIBER project.