Necrotic leaf blotch
Disease
Necrotic leaf blotch
Physiological disorder
Distribution: This is a physiological disorder affecting only Golden Delicious and its bud sports.
Photos
This disorder can be confused with magnesium deficiency (shown).
Mid-Atlantic Orchard Monitoring Guide
C
Medium to large, irregular necrotic lesions occur on the foliage of mature leaves during mid- to late summer. The remaining green tissue generally turns yellow shortly after the appearance of symptoms (A, B). The onset of symptoms is often sudden and occurs in 2 to 4 waves during the summer. Defoliation rapidly follows the onset of symptoms and may affect fruit quality if it is extensive.