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Alternaria leaf blight

Michelle Grabowski, University of Minnesota, Extension Educator

Alternaria leaf blight is caused by the fungus Alternaria cucumerina. This disease is most problematic on melon but can also occur on cucumber, pumpkin and squash. Alternaria leaf blight does not commonly infect fruit but can reduce yield and quality through reduced plant vigor and sunscald of exposed fruit.


M. Grabowski, University of Minnesota


Important biology

Alternaria cucumerina can be carried long distance on wind currents and can be spread within the field by splashing water. Wet rainy weather favors diseases, and damage can be very severe in warm, wet conditions. The fungus survives from season to season in plant debris.



G. Holmes, CA Poly Tech

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