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: Bacterial mushy canker
HOST: Papaya
This disease (Micronesia) differs from bacterial decline by causing blackish, water-soaked, mushy cankers near or in leaf axils or on young stems.

Bacterial mushy canker | Papaya
DISEASE: Bacterial mushy canker
HOST: Papaya (Carica papaya)
PATHOGEN: Erwinia sp.
SOURCE: E. Trujillo
DISEASE: Xanthomonas leaf spot
HOST: Cabbage
Cabbage leaf with small lesions. Lesions may enlarge and coalesce, causing distortion. Stem lesions are black and sunken and may cause death of the plants.

Xanthomonas leaf spot | Cabbage
DISEASE: Xanthomonas leaf spot
HOST: Cabbage (Brassica oleracea var. capitata)
PATHOGEN: Xanthomonas campestris pv. raphani
SOURCE: R. Gitaitis