DISEASE: Bacterial blast and black pit
HOST: Citrus (Lemon)
The term "black pit" refers to black lesions on fruit, which may be specks or large, sunken pits as seen here. They also may be light tan, later becoming reddish brown to black.

Bacterial blast and black pit | Citrus (Lemon)
DISEASE: Bacterial blast and black pit
HOST: Citrus (Lemon) (Citrus limon)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: J. Menge
DISEASE: Bacterial blast and black pit
HOST: Citrus (Lime)
Characteristic symptoms of brownish black lesions on twigs and leaves (blast), starting with infection of petioles. Black pit refers to brown to black sunken spots on fruit, 5 to 20 mm in diameter.

Bacterial blast and black pit | Citrus (Lime)
DISEASE: Bacterial blast and black pit
HOST: Citrus (Lime) (Citrus sp.)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: P. Broadbent
DISEASE: Bacterial leaf blight and stalk rot
HOST: Corn (Maize)
Corn husk leaves with brownish red streaks and blotches. The leaves turn brown but may later become gray or white. Symptoms vary depending upon genotype.

Bacterial leaf blight and stalk rot | Corn (Maize)
DISEASE: Bacterial leaf blight and stalk rot
HOST: Corn (Maize) (Zea mays)
PATHOGEN: Acidovorax avenae
PATHOGEN SYNONYM: Acidovorax avenae subsp. avenae
SOURCE: A. Alvarez
DISEASE: Bacterial leaf blight and stalk rot
HOST: Corn (Maize)
Leaves with whitish streaks.

Bacterial leaf blight and stalk rot | Corn (Maize)
DISEASE: Bacterial leaf blight and stalk rot
HOST: Corn (Maize) (Zea mays)
PATHOGEN: Acidovorax avenae
PATHOGEN SYNONYM: Acidovorax avenae subsp. avenae
SOURCE: R. Gitaitis
DISEASE: Bacterial leaf blight and stalk rot
HOST: Corn (Maize)
Lesions may vary from brown to red, sometimes gray or white, and some genotypes have red borders around lesions.

Bacterial leaf blight and stalk rot | Corn (Maize)
DISEASE: Bacterial leaf blight and stalk rot
HOST: Corn (Maize) (Zea mays)
PATHOGEN: Acidovorax avenae
PATHOGEN SYNONYM: Acidovorax avenae subsp. avenae
SOURCE: R. Gitaitis
DISEASE: Elm yellows
HOST: Elm
Symptoms of elm yellows occasionally appear on one branch before others, but more often they involve the entire crown.

Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus americana)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair
DISEASE: Elm yellows
HOST: Elm
Diseased twig (right) with epinasty, chlorosis, and yellowing of leaves. Sometimes both yellow and green leaves occur on same branch. Healthy branch (left).

Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus americana)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair
DISEASE: Elm yellows
HOST: Elm
Branches with butterscotch discoloration (center) and necrotic flecks in phloem and vascular cambium (right). Healthy branch (left). Sudden wilt and browning is common with small trees.

Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus americana)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair
DISEASE: Elm yellows
HOST: Elm
Elm yellows is characterized by witches'-brooms and stunting. Some cultivars have both yellow and reddish foliar discoloration.

Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus parvifolia)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair