Zebra Chip Disease Profiles I - Foliar Symptoms

A new disease of potato exhibiting the foliar symptoms of yellowing, purpling, and distortion was first observed around Saltillo, Mexico in 1994, before being reported in the U.S. in 2000 in south Texas, where it caused substantial losses to both producers and processors in 2004-2005. The most distinguishing characteristic is a discoloration of sliced tubers after frying, resulting in the name “Zebra Chip.” The disease is now known to be present throughout Latin America and has been reported from at least eight states in the U.S., including Nebraska.
The pathogen causing Zebra Chip is transmitted to plants by the potato-tomato psyllid, Bactericera cockerelli. The most recent research to date strongly suggests the pathogen to be the fastidious bacterium ‘Candidatus Liberibacter solanacearum’. It is limited to the phloem of plants, thus resulting in numerous symptoms associated with a disease of the vascular system.