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Necrotic Leaf Blotch (Golden Leaf Drop)

Non-pathogenic (physiological)

12 host plants

Last updated

Data Coverage 3 of 6 dimensions
Causal Agent
Host Plants
Symptoms
Management
GDD Threshold
Regional Notes

Golden Delicious apples develop irregular necrotic blotches on mature leaves that yellow and drop in waves. This physiological disorder follows cool, rainy periods succeeded by hot, sunny weather. Trees on M9 or M26 rootstocks show less incidence. Zinc oxide (3-4 sprays) and foliar manganese reduce symptoms.

Reduce moisture around affected tissue by improving drainage and air circulation. Remove rotted material cleanly and dispose of it away from the planting area. Avoid wounding healthy tissue during cleanup, as fresh wounds create new entry points. If the problem keeps returning, evaluate whether the site is too wet or poorly drained for the species you are growing.

Quick Reference

Causal Agent
Non-pathogenic (physiological)
Host Plants
12

Management

Cultural Controls

  • Incidence of this problem is less when grown on M9 or M26 rootstocks.
  • Zinc oxide applied in 3 to 4 cover sprays can reduce symptoms.
  • Two foliar applications of manganese can reduce symptoms.

Host Plants (12)