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 of beet
HOST: Beet
Beet leaves with spots and marginal necrosis.

Bacterial leaf spot of beet | Beet
DISEASE: Bacterial leaf spot of beet
HOST: Beet (Beta vulgaris subsp. vulgaris)
PATHOGEN: Pseudomonas syringae pv. aptata
PATHOGEN SYNONYM: Pseudomonas aptata
SOURCE: P. Brown
DISEASE: Bacterial wilt and dieback
HOST: Willow
Cross sections of the characteristic "watermark stain" of diseased wood. Wilt and dieback occur as disease progresses.

Bacterial wilt and dieback | Willow
DISEASE: Bacterial wilt and dieback
HOST: Willow (Salix sp.)
PATHOGEN: Brenneria salicis
PATHOGEN SYNONYM: Erwinia salicis
SOURCE: Y. Sakamoto, M. Goto