2007 Annual Report 1a.Objectives (from AD-416) Investigate the role of the potato psyllid in Zebra Chip potato disease. 1b.Approach (from AD-416) Conduct field cage experiments and laboratory transmission studies. Documents Trust with Frito-Lay/Zebra Chip Grower Research Group. 425 Log 32739. 3.Progress Report This report serves to document research conducted under a Trust agreement between ARS and Frito-Lay. Additional details of research can be found in the report of the parent project 5352-22000-016-00D 'Biorational Control Methods for Insect Pests of Potato'. A series of laboratory and field experiments were conducted to investigate the causal agents and vectors of zebra chip, a new defect of potato that has recently been documented in several southwestern states of the United States, Mexico, and Central America. This defect is causing millions of dollars in losses to both potato producers and processors. Results revealed that this potato disease is associated with the potato psyllid. Potato growers affected by zebra chip will be able to minimize the losses due to this disease by focusing efforts on monitoring and controlling the potato psyllid. ADODR STATEMENT: Monitoring of activities and progress on this project was accomplished by direct supervision of on site employees, and use of e-mail and telephone to communicate with off site collaborators.