DISEASE: Bacterial leaf scorch
HOST: Pecan
Pecan with necrotic scorched leaves with distinct dark lines between healthy and diseased tissues.

Bacterial leaf scorch | Pecan
DISEASE: Bacterial leaf scorch
HOST: Pecan (Carya illinoinensis)
PATHOGEN: Xylella fastidiosa
SOURCE: T. Brenneman
DISEASE: Bacterial leaf scorch
HOST: Sycamore
Sycamore with scorched leaves and dieback of small branches.

Bacterial leaf scorch | Sycamore
DISEASE: Bacterial leaf scorch
HOST: Sycamore (Platanus occidentalis)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Bacterial leaf scorch
HOST: Sycamore
Close-up of scorched leaves.

Bacterial leaf scorch | Sycamore
DISEASE: Bacterial leaf scorch
HOST: Sycamore (Platanus occidentalis)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Bermudagrass white leaf
HOST: Grass
White leaf disease of bermudagrass.

Bermudagrass white leaf | Grass
DISEASE: Bermudagrass white leaf
HOST: Grass (Cynodon transvaalensis)
PATHOGEN: 'Candidatus Phytoplasma cynodontis'
PATHOGEN SYNONYM: Phytoplasma Bermuda white leaf group
SOURCE: M. Davis
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