DISEASE: Crown gall (Leafy gall)
HOST: Datura
Crown gall or leafy gall of datura.

Crown gall (Leafy gall) | Datura
DISEASE: Crown gall (Leafy gall)
HOST: Datura (Datura sp.)
PATHOGEN: Agrobacterium tumefaciens
PATHOGEN SYNONYM: Rhizobium sp.
SOURCE: M. Schroth
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: Xanthomonas leaf blight
HOST: Onion
This was the first photo of onion leaf blight, which was considered a controversial finding for 10 years until an outbreak occurred in the West Indies.

Xanthomonas leaf blight | Onion
DISEASE: Xanthomonas leaf blight
HOST: Onion (Allium cepa)
PATHOGEN: Xanthomonas axonopodis pv. allii
PATHOGEN SYNONYM: Xanthomonas campestris pv. allii
SOURCE: A. Alvarez
DISEASE: Xanthomonas leaf blight
HOST: Onion
Diseased leaf with necrotic internal tissues.

Xanthomonas leaf blight | Onion
DISEASE: Xanthomonas leaf blight
HOST: Onion (Allium cepa)
PATHOGEN: Xanthomonas axonopodis pv. allii
PATHOGEN SYNONYM: Xanthomonas campestris pv. allii
SOURCE: A. Alvarez
DISEASE: Xanthomonas leaf blight
HOST: Onion
Onions with brown, necrotic, blighted leaves.

Xanthomonas leaf blight | Onion
DISEASE: Xanthomonas leaf blight
HOST: Onion (Allium cepa)
PATHOGEN: Xanthomonas axonopodis pv. allii
PATHOGEN SYNONYM: Xanthomonas campestris pv. allii
SOURCE: H. Schwartz
DISEASE: Xanthomonas leaf blight
HOST: Onion
Onions with severely blighted leaves.

Xanthomonas leaf blight | Onion
DISEASE: Xanthomonas leaf blight
HOST: Onion (Allium cepa)
PATHOGEN: Xanthomonas axonopodis pv. allii
PATHOGEN SYNONYM: Xanthomonas campestris pv. allii
SOURCE: H. Schwartz