DISEASE: Alfalfa dwarf
HOST: Alfalfa
Alfalfa dwarf is characterized by stunted plants (left), usually dark blue-green in color. Xylem tissues become brown, especially when exposed to air.

Alfalfa dwarf | Alfalfa
DISEASE: Alfalfa dwarf
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xylella fastidiosa
SOURCE: R. M. Davis
DISEASE: Angular leaf spot
HOST: Pumpkin
Leaf with lesions surrounded by light greenish halos.

Angular leaf spot | Pumpkin
DISEASE: Angular leaf spot
HOST: Pumpkin (Cucurbita pepo)
PATHOGEN: Pseudomonas syringae pv. lachrymans
SOURCE: A. Simkus, M. Shurtleff
DISEASE: Bacterial blight
HOST: Photinia
Symptoms of photinia bud blight shown here are similar to those of blast of pear and apple, caused by Pseudomonas syringae pv. syringae.

Bacterial blight | Photinia
DISEASE: Bacterial blight
HOST: Photinia (Photinia glabra)
PATHOGEN: Pseudomonas syringae pv. photiniae
SOURCE: M. Goto
DISEASE: Bacterial fruit blotch
HOST: Pumpkin
Pumpkin exhibiting early stage of disease on rind.

Bacterial fruit blotch | Pumpkin
DISEASE: Bacterial fruit blotch
HOST: Pumpkin (Cucurbita pepo)
PATHOGEN: Acidovorax citrulli
PATHOGEN SYNONYM: Acidovorax avenae subsp. citrulli
SOURCE: R. Gitaitis
DISEASE: Bacterial fruit blotch
HOST: Pumpkin
Leaves with large necrotic areas.

Bacterial fruit blotch | Pumpkin
DISEASE: Bacterial fruit blotch
HOST: Pumpkin (Cucurbita pepo)
PATHOGEN: Acidovorax citrulli
PATHOGEN SYNONYM: Acidovorax avenae subsp. citrulli
SOURCE: R. Gitaitis
DISEASE: Bacterial fruit blotch
HOST: Pumpkin
Severe internal rot.

Bacterial fruit blotch | Pumpkin
DISEASE: Bacterial fruit blotch
HOST: Pumpkin (Cucurbita pepo)
PATHOGEN: Acidovorax citrulli
PATHOGEN SYNONYM: Acidovorax avenae subsp. citrulli
SOURCE: R. Gitaitis
DISEASE: Bacterial fruit blotch
HOST: Pumpkin
Severe internal rot.

Bacterial fruit blotch | Pumpkin
DISEASE: Bacterial fruit blotch
HOST: Pumpkin (Cucurbita pepo)
PATHOGEN: Acidovorax citrulli
PATHOGEN SYNONYM: Acidovorax avenae subsp. citrulli
SOURCE: R. Gitaitis
DISEASE: Bacterial leaf spot
HOST: Alfalfa
Stems with necrotic lesions.

Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: APS
DISEASE: Bacterial leaf spot
HOST: Alfalfa
Leaves with brown necrotic spots. Stems have water-soaked spots.

Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: S. Thomson