DISEASE: Bacterial leaf streak and stripe
HOST: Grass
Vasey grass with yellowish to brownish red streaks and stripes.

Bacterial leaf streak and stripe | Grass
DISEASE: Bacterial leaf streak and stripe
HOST: Grass (Paspalum urvillei)
PATHOGEN: Acidovorax avenae
PATHOGEN SYNONYM: Acidovorax avenae subsp. avenae
SOURCE: R. Gitaitis
DISEASE: Elm leaf scorch
HOST: Elm
Diseased tree with scorch at leaf margins.

Elm leaf scorch | Elm
DISEASE: Elm leaf scorch
HOST: Elm (Ulmus americana)
PATHOGEN: Xylella fastidiosa
SOURCE: J. Sherald, M. Shurtleff
DISEASE: Elm leaf scorch
HOST: Elm
Severely diseased tree with dieback and scorched leaves.

Elm leaf scorch | Elm
DISEASE: Elm leaf scorch
HOST: Elm (Ulmus americana)
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