DISEASE: Marginal leaf blight
HOST: Lettuce
Marginal leaf blight first appears as slimy wilting of leaf margins. Small, reddish lesions may be seen on leaf blades. Infected tissues turn brown to black in time.
Marginal leaf blight | Lettuce
DISEASE: Marginal leaf blight
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Pseudomonas marginalis
SOURCE: L. Fucikovsky
DISEASE: Oak leaf scorch
HOST: Oak
Oak with scorched leaf tips.
Oak leaf scorch | Oak
DISEASE: Oak leaf scorch
HOST: Oak (Quercus kelloggii)
PATHOGEN: Xylella fastidiosa
SOURCE: S. Kostka
DISEASE: Oak leaf scorch
HOST: Oak
Leaf with brown, marginal necrosis resembling a burn.
Oak leaf scorch | Oak
DISEASE: Oak leaf scorch
HOST: Oak (Quercus rubra)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Oak leaf scorch
HOST: Oak
Diseased tree with brownish, scorched leaves.
Oak leaf scorch | Oak
DISEASE: Oak leaf scorch
HOST: Oak (Quercus rubra)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Varnish spot
HOST: Lettuce
Leaf with large brown and small, shiny, dark brown necrotic spots that spread in size and later dry out.
Varnish spot | Lettuce
DISEASE: Varnish spot
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Pseudomonas cichorii
SOURCE: S. Miller
DISEASE: Varnish spot
HOST: Lettuce
Advanced stage of disease with large, brown necrotic areas. They most often are along veins. Outermost leaves of the head usually are not affected.
Varnish spot | Lettuce
DISEASE: Varnish spot
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Pseudomonas cichorii
SOURCE: K. Ohata, M. Goto