A fungal disease of Lettuce that shows as tiny black spots on the leaves initially that turn yellow then brown with a reddish margin as they increase in size up to 4 mm diameter. The centres may dry and fall out leaving holes in the leaf. Pink spores may be formed in the sunken centres of the lesion. Heavily infects plants may be stunted.
Favoured by cool wet weather.
Origin and History:
Management and Control:
Use uninfected seed.
Rotate to resistant crops and increase the time between successive Lettuce crops.
Remove and destroy infected Lettuce plants.
Destroy crop residues.
Related and Similar Species:
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