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 foot rot
HOST: Rice
The disease causes sheaths to turn dark brown and rot; dead leaves droop. Nodes, culms, and crowns also decay, and infected tillers are easily detached from the crown. Culms and internodes turn black.

Bacterial foot rot | Rice
DISEASE: Bacterial foot rot
HOST: Rice (Oryza sativa)
PATHOGEN: Dickeya zeae
PATHOGEN SYNONYM: Erwinia chrysanthemi pv. zeae
SOURCE: M. Goto
DISEASE: Bacterial foot rot
HOST: Rice
Decayed culms (right) and healthy culms (left). Leaf sheaths of infected plants exhibit dark brown decay and attached leaves turn yellow and wilt.

Bacterial foot rot | Rice
DISEASE: Bacterial foot rot
HOST: Rice (Oryza sativa)
PATHOGEN: Dickeya zeae
PATHOGEN SYNONYM: Erwinia chrysanthemi pv. zeae
SOURCE: M. Goto
DISEASE: Tomato big bud
HOST: Tomato
Characteristic symptoms are swollen, apical stems and stunted leaves. Apical stems are generally thickened and assume a stiff and erect growth habit. Internodes are shortened and flower buds are greatly enlarged.

Tomato big bud | Tomato
DISEASE: Tomato big bud
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: D. Teakle
DISEASE: Tomato big bud
HOST: Tomato
Symptoms are enlarge sepals that do not separate. Flower buds stay green and do not develop into fruit. Leaves are small and chlorotic.

Tomato big bud | Tomato
DISEASE: Tomato big bud
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson
DISEASE: Tomato big bud
HOST: Tomato
Abnormal flower bud with greatly enlarged sepals. Sepals do not separate, fruit is not produced, and apical growth is upright.

Tomato big bud | Tomato
DISEASE: Tomato big bud
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson