DISEASE: Aster yellows
HOST: Squash
Diagnostic characteristics for the disease are yellowing of young leaves, proliferation of secondary shoots, and rigid erect habit. Leaves are misshapen and smaller than normal and have stiff, thick laminae.

Aster yellows | Squash
DISEASE: Aster yellows
HOST: Squash (Cucurbita sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Miller
DISEASE: Bacterial blight (Bacterial necrosis)
HOST: Grape
Stem necrosis of grape.

Bacterial blight (Bacterial necrosis) | Grape
DISEASE: Bacterial blight (Bacterial necrosis)
HOST: Grape (Vitis vinifera)
PATHOGEN: Xylophilus ampelinus
PATHOGEN SYNONYM: Xanthomonas ampelina
SOURCE: N. Schaad
DISEASE: Bacterial blight (Bacterial necrosis)
HOST: Grape
Stem with cankers and discolored external tissues.

Bacterial blight (Bacterial necrosis) | Grape
DISEASE: Bacterial blight (Bacterial necrosis)
HOST: Grape (Vitis vinifera)
PATHOGEN: Xylophilus ampelinus
PATHOGEN SYNONYM: Xanthomonas ampelina
SOURCE: N. Schaad
DISEASE: Bacterial blight (Bacterial necrosis)
HOST: Grape
Severe infection in vineyard is noted by dead canes. Symptoms are most severe in spring; shoot blight, occasional spots on leaves, and cankers are common.

Bacterial blight (Bacterial necrosis) | Grape
DISEASE: Bacterial blight (Bacterial necrosis)
HOST: Grape (Vitis vinifera)
PATHOGEN: Xylophilus ampelinus
PATHOGEN SYNONYM: Xanthomonas ampelina
SOURCE: C. Manceau, N. Schaad
DISEASE: Bacterial blight (Bacterial necrosis)
HOST: Grape
Leaf with necrotic spots and marginal necrosis. One-sided cracking of petiole tissue is common (not shown here).

Bacterial blight (Bacterial necrosis) | Grape
DISEASE: Bacterial blight (Bacterial necrosis)
HOST: Grape (Vitis vinifera)
PATHOGEN: Xylophilus ampelinus
PATHOGEN SYNONYM: Xanthomonas ampelina
SOURCE: C. Panagopoulos
DISEASE: Bacterial leaf spot (Blight)
HOST: Beet
Seedling blight stage of the disease.

Bacterial leaf spot (Blight) | Beet
DISEASE: Bacterial leaf spot (Blight)
HOST: Beet (Beta vulgaris)
PATHOGEN: Pseudomonas syringae pv. aptata
PATHOGEN SYNONYM: Pseudomonas aptata
SOURCE: C. Schneider
DISEASE: Bacterial leaf spot (Blight)
HOST: Beet
Leaves with dark brown necrotic regions and streaks; two petioles also are infected.

Bacterial leaf spot (Blight) | Beet
DISEASE: Bacterial leaf spot (Blight)
HOST: Beet (Beta vulgaris)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: C. Schneider
DISEASE: Bacterial pocket
HOST: Beet
Sugar beets with many small tubercles at infection sites.

Bacterial pocket | Beet
DISEASE: Bacterial pocket
HOST: Beet (Beta vulgaris)
PATHOGEN: Xanthomonas axonopodis pv. betlicola
PATHOGEN SYNONYM: Xanthomonas campestris pv. betlicola
SOURCE: C. Schneider
DISEASE: Bacterial vascular necrosis and rot
HOST: Beet
Cross section of sugar beet with reddish color in vascular bundles and adjacent tissues.

Bacterial vascular necrosis and rot | Beet
DISEASE: Bacterial vascular necrosis and rot
HOST: Beet (Beta vulgaris)
PATHOGEN: Pectobacterium betavasculorum
PATHOGEN SYNONYM: Erwinia carotovora subsp. betavasculorum
SOURCE: M. Schroth