PM 7/20 (3) <i>Erwinia amylovora</i>

Symptomatic samples can be processed individually or in small batches combining material from several samples (see Appendix, ). Precautions to avoid cross-contamination should be taken when collecting samples and during the extraction process. Samples with symptoms for diagnosis of fire blight should preferably be composed of flowers, shoots or twigs, leaves, fruitlets (with necrosis and/or with exudates), or the discoloured subcortical tissues (after peeling bark from cankers in branches, trunk or collar). Samples should be processed as soon as possible after collection but can be kept at 4–8°C for up to 1 week before analysis, if necessary.