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 leaf spot
HOST: Alfalfa
Stems with necrotic lesions.

Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: APS
DISEASE: Bacterial leaf spot
HOST: Alfalfa
Leaves with brown necrotic spots. Stems have water-soaked spots.

Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: S. Thomson
DISEASE: Bacterial leaf spot
HOST: Alfalfa
Leaves with both water-soaked and necrotic spots.

Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: APS
DISEASE: Bacterial leaf spot
HOST: Alfalfa
Leaves with necrotic, brownish paperlike areas.

Bacterial leaf spot | Alfalfa
DISEASE: Bacterial leaf spot
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xanthomonas alfalfae subsp. alfalfae
PATHOGEN SYNONYM: Xanthomonas campestris pv. alfalfae
SOURCE: APS
DISEASE: Bacterial leaf spot
HOST: Pellionia
Leaves with dry, irregularly shaped lesions with corky, raised borders on upper surface.

Bacterial leaf spot | Pellionia
DISEASE: Bacterial leaf spot
HOST: Pellionia (Pellionia sp.)
PATHOGEN: Xanthomonas campestris
SOURCE: A. Chase
DISEASE: Bacterial leaf spot
HOST: Pellionia
Leaf lesions are irregular, corky, and slightly raised on lower leaf surfaces. Lesions may fall out, leaving a shot-hole appearance.

Bacterial leaf spot | Pellionia
DISEASE: Bacterial leaf spot
HOST: Pellionia (Pellionia sp.)
PATHOGEN: Xanthomonas campestris
SOURCE: H. Schwartz
DISEASE: Bacterial soft rot (Cladode rot)
HOST: Cactus
Brown necrotic areas of cladodes of Christmas cactus.

Bacterial soft rot (Cladode rot) | Cactus
DISEASE: Bacterial soft rot (Cladode rot)
HOST: Cactus (Schlumbergera × buckleyi)
PATHOGEN: Pectobacterium carotovorum
PATHOGEN SYNONYM: Erwinia carotovora subsp. carotovora
SOURCE: A. Alvarez