Meaning of apple rust in English:
apple rust
noun
Any of several rust fungi of the genus Gynosporangium, especially G. juniperivirginianae, which alternately infects red cedar (Juniperus virginiana) and the apple; the disease caused by this, resulting (in the apple) in lesions on the leaves and distorted fruit.
Origin
Late 19th century; earliest use found in The Botanical Gazette.
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