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 brown rot
HOST: Orchid
Phalaenopsis orchid with yellowish brown spot on leaf (left), an early stage of disease.

Bacterial brown rot | Orchid
DISEASE: Bacterial brown rot
HOST: Orchid (Phalaenopsis sp.)
PATHOGEN: Acidovorax cattleyae
PATHOGEN SYNONYM: Acidovorax avenae subsp. cattleyae
SOURCE: R. McMillan
DISEASE: Bacterial brown rot
HOST: Orchid
Leaves of Phalaenopsis orchid with advanced stage of decay.

Bacterial brown rot | Orchid
DISEASE: Bacterial brown rot
HOST: Orchid (Phalaenopsis sp.)
PATHOGEN: Acidovorax cattleyae
PATHOGEN SYNONYM: Acidovorax avenae subsp. cattleyae
SOURCE: R. McMillan
DISEASE: Bacterial bud and petal blight
HOST: Orchid
Miltonia orchid with brownish necrotic areas around edges of flower petals.

Bacterial bud and petal blight | Orchid
DISEASE: Bacterial bud and petal blight
HOST: Orchid (Miltonia sp.)
PATHOGEN: Acidovorax cattleyae
SOURCE: R. Raabe
DISEASE: Bacterial bud and petal blight
HOST: Orchid
Miltonia orchid with diseased water-soaked flower buds.

Bacterial bud and petal blight | Orchid
DISEASE: Bacterial bud and petal blight
HOST: Orchid (Miltonia sp.)
PATHOGEN: Acidovorax cattleyae
SOURCE: R. Raabe
DISEASE: Bacterial fruit blotch
HOST: Watermelon
Symptoms of external disease of mature watermelon.

Bacterial fruit blotch | Watermelon
DISEASE: Bacterial fruit blotch
HOST: Watermelon (Citrullus lanatus)
PATHOGEN: Acidovorax citrulli
PATHOGEN SYNONYM: Acidovorax avenae subsp. citrulli
SOURCE: R. X. Latin
DISEASE: Bacterial fruit blotch
HOST: Watermelon
Diseased watermelon with copious white foam.

Bacterial fruit blotch | Watermelon
DISEASE: Bacterial fruit blotch
HOST: Watermelon (Citrullus lanatus)
PATHOGEN: Acidovorax citrulli
PATHOGEN SYNONYM: Acidovorax avenae subsp. citrulli
SOURCE: R. Gitaitis
DISEASE: Bacterial leaf and stem necrosis
HOST: Watermelon
Seedlings with necrotic leaves and water-soaked stems.

Bacterial leaf and stem necrosis | Watermelon
DISEASE: Bacterial leaf and stem necrosis
HOST: Watermelon (Citrullus lanatus)
PATHOGEN: Pseudomonas viridiflava
SOURCE: Y. Aysan
DISEASE: Bacterial leaf blight and rot
HOST: Orchid
Leaves of Dendrobium orchid with necrosis, discoloration, and rot.

Bacterial leaf blight and rot | Orchid
DISEASE: Bacterial leaf blight and rot
HOST: Orchid (Dendrobium sp.)
PATHOGEN: Burkholderia gladioli pv. gladioli
PATHOGEN SYNONYM: Pseudomonas gladioli pv. gladioli
SOURCE: L. Keith