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: Aster yellows
HOST: Ranunculus
Malformation of diseased flower.

Aster yellows | Ranunculus
DISEASE: Aster yellows
HOST: Ranunculus (Ranunculus sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Raabe
DISEASE: Bacterial leaf spot (Blight)
HOST: Ranunculus
Leaf with large, brown necrotic areas delimited by veins.

Bacterial leaf spot (Blight) | Ranunculus
DISEASE: Bacterial leaf spot (Blight)
HOST: Ranunculus (Ranunculus sp.)
PATHOGEN: Xanthomonas campestris
SOURCE: R. Raabe
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 scab
HOST: Gladiolus
Gladiolus bulb with brownish to dark brown, sunken scabs.

Bacterial scab | Gladiolus
DISEASE: Bacterial scab
HOST: Gladiolus (Gladiolus sp.)
PATHOGEN: Burkholderia gladioli pv. gladioli
PATHOGEN SYNONYM: Pseudomonas gladioli pv. gladioli
SOURCE: Plant Protection Service of the Netherlands