Germplasm should reach the unit in August. Potatoes that are free of pathogens will be released from quarantine by late spring. Vegetatively-propagated potatoes will be distributed to each designated recipient as 3-4 in vitro plantlets. Healthy seed lots, less the seeds removed for testing purposes, will be distributed to recipients. Infected seed lots will be destroyed. Infected, vegetatively-propagated potatoes will be subjected to chemo- and thermotherapeutic treatments for the elimination of pathogens and then retested to ensure the success of the therapy. This process may add a year to the duration of the quarantine period.