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: Dodonaea yellows
HOST: Florida hopbush
Hopbush with brownish red witches'-broom.

Dodonaea yellows | Florida hopbush
DISEASE: Dodonaea yellows
HOST: Florida hopbush (Dodonaea viscosa)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: W. Borth
DISEASE: Dodonaea yellows
HOST: Florida hopbush
Advanced stage of dodonaea yellows and witches'-broom.

Dodonaea yellows | Florida hopbush
DISEASE: Dodonaea yellows
HOST: Florida hopbush (Dodonaea viscosa)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: W. Borth
DISEASE: Syringae leaf spot
HOST: Tomato
Leaves with brown necrotic lesions and chlorotic margins. Symptoms vary greatly among cultivars. Some have black or brown lesions with bright yellow, chlorotic areas and others do not have yellowing.

Syringae leaf spot | Tomato
DISEASE: Syringae leaf spot
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: R. Gitaitis