2011 Annual Report 1a.Objectives (from AD-416) Develop new monoclonal antibodies that can be used for rapid detection and identification of Potato virus Y (PVY) strains that can be utilized on a large scale by certification agencies, researchers, and diagnostic facilities. 1b.Approach (from AD-416) Nucleoproteins of diverse strains of PVY will be purified using standard methods. These will be used to immunize mice for production of monoclonal antibodies (MAbs) by hybridoma technology. The MAbs will be tested for virus strain specificity using a large panel of characterized PVY isolates available to the cooperator. 3.Progress Report Potato virus Y (PVY) is the most important virus of potato and reduces both yield and quality of potato tubers. Some PVY isolates cause necrosis (death) of potato tuber tissue and these viruses have become more important in North America and Europe in the last ten years. Because PVY occurs as a number of different genetic strains, reliable detection and identification is critical in efforts to control this virus. ARS and University researchers have been developing new antibodies to PVY that are capable of sensitive detection and identification of many of these virus strains. This capability will aid researchers, seed certification agencies, and diagnostic laboratories to rapidly detect and correctly identify strains of PVY. This project investigates the molecular and biological differences among isolates of potato virus Y which contributes directly to objective 2 of the in-house project. The project was monitored by email and phone converstions, and discussions at the annual potato virus meeting.