·         Development of a standardized procedure for detection of eleven viruses and one viroid of potatoes.

·         Determined that the potato purple top phytoplasma is tuber-borne at a relatively high rate in major potato cultivars.

·         Demonstrated that various strains of Potato virus Y (PVY) are widespread in certified seed potatoes grown in the US and Canada.

·         Reported the occurrence of potato mop top virus (PMTV) for the first time in Washington State.

·         Potato zebra chip disease was found for the first time in Washington, Oregon, and Idaho in 2011.