Bacterial and fungal canker:A wide range of nursery stock can be susceptible to potential damage from various cankers

摘要

:Cankers in nursery stock species are characterised by the death of cambium (inner bark) tissue of woody stems, branches or twigs, causing them to sink in. They can completely girdle the stem, disrupting the vascular system so that shoots beyond the canker wilt and die through a lack of water. Large numbers of smaller cankers can also disrupt vascular systems enough to cause gradual wilting and shoot death.The most common canker pathogens are the fungus Nectria galligena, which causes cankers on subjects such as apple, pear, willow, mountain ash, beech and poplar, and the bacterium Pseudomonas syringae, which exists as a large number of subspecies and cancause cankers in a wide range of trees and shrubs.