Published online by Cambridge University Press: 27 March 2009
Progeny tests for resistance to potato leafroll virus using true seedlings in a glasshouse in Scotland ranked progenies by the percentages of seedlings showing primary symptoms, in accordance with the known phenotypes of their parents. Symptoms were more obvious in seedlings grown under sodium lamps than in those grown under fluorescent strip lights. These glasshouse seedling progeny tests were then evaluated by comparing them with field clonal trials. The progeny tests were found to identify effectively those progenies most resistant to potato leafroll virus but were not effective for identifying the most resistant clones within progenies.