DISEASE: Bacterial leaf spot of chard
HOST: Chard
Chard leaves with necrotic spots.

Bacterial leaf spot of chard | Chard
DISEASE: Bacterial leaf spot of chard
HOST: Chard (Beta vulgaris subsp. cicla)
PATHOGEN: Pseudomonas syringae pv. aptata
PATHOGEN SYNONYM: Pseudomonas aptata
SOURCE: P. Brown
DISEASE: Bacterial leaf spot of chard
HOST: Chard
Chard with necrotic, irregular leaf spots.

Bacterial leaf spot of chard | Chard
DISEASE: Bacterial leaf spot of chard
HOST: Chard (Beta vulgaris subsp. cicla)
PATHOGEN: Pseudomonas syringae pv. aptata
PATHOGEN SYNONYM: Pseudomonas aptata
SOURCE: P. Brown
DISEASE: Bacterial leaf spot
HOST: Elm
Leaf with small, dark brown lesions and necrosis along veins.

Bacterial leaf spot | Elm
DISEASE: Bacterial leaf spot
HOST: Elm (Ulmus americana)
PATHOGEN: Pseudomonas syringae pv. ulmi
SOURCE: W. Sinclair
DISEASE: Bacterial wilt
HOST: Muskmelon
Severely diseased plants as noted by dying runners.

Bacterial wilt | Muskmelon
DISEASE: Bacterial wilt
HOST: Muskmelon (Cucumis melo)
PATHOGEN: Erwinia tracheiphila
SOURCE: M. Shurtleff
DISEASE: Bacterial wilt
HOST: Muskmelon
Wilt-devastated muskmelon field.

Bacterial wilt | Muskmelon
DISEASE: Bacterial wilt
HOST: Muskmelon (Cucumis melo)
PATHOGEN: Erwinia tracheiphila
SOURCE: M. Shurtleff
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: 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