DISEASE: Bacterial wilt
HOST: Alfalfa
Longitudinal section of defined brown gum pockets on inner surface of root bark.

Bacterial wilt | Alfalfa
DISEASE: Bacterial wilt
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Clavibacter michiganensis subsp. insidiosus
SOURCE: S. Thomson
DISEASE: Bacterial wilt
HOST: Alfalfa
Infected plant (left) with typical symptoms of stunting and chlorosis. Other characteristic symptoms are spindly stems and small distorted leaflets. Healthy plant (right).

Bacterial wilt | Alfalfa
DISEASE: Bacterial wilt
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Clavibacter michiganensis subsp. insidiosus
SOURCE: S. Thomson
DISEASE: Bacterial wilt
HOST: Alfalfa
Diseased plant with chlorotic leaves.

Bacterial wilt | Alfalfa
DISEASE: Bacterial wilt
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Clavibacter michiganensis subsp. insidiosus
SOURCE: S. Thomson
DISEASE: Bacterial wilt
HOST: Alfalfa
Cross sections of diseased roots with defined brown gum pockets on inner surface of bark. Healthy root (upper left). Other sections represent increases in disease severity.

Bacterial wilt | Alfalfa
DISEASE: Bacterial wilt
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Clavibacter michiganensis subsp. insidiosus
SOURCE: L. Claflin
DISEASE: Multiplier disease
HOST: Strawberry
Multiplier disease causes production of numerous crowns along runners.

Multiplier disease | Strawberry
DISEASE: Multiplier disease
HOST: Strawberry (Fragaria × ananassa)
PATHOGEN: 'Candidatus Phytoplasma trifolii'
PATHOGEN SYNONYM: Phytoplasma Clover proliferation group
SOURCE: M. Clark
DISEASE: Sour skin
HOST: Onion
Symptoms of sour skin are characterized by slimy, pale yellow to light brown decay.

Sour skin | Onion
DISEASE: Sour skin
HOST: Onion (Allium cepa)
PATHOGEN: Burkholderia cepacia
PATHOGEN SYNONYM: Pseudomonas cepacia
SOURCE: Dep. of Agric. & Agri-Food, Government of Canada
DISEASE: Sour skin
HOST: Onion
Characteristic pale yellow to browning of infected area.

Sour skin | Onion
DISEASE: Sour skin
HOST: Onion (Allium cepa)
PATHOGEN: Burkholderia cepacia
PATHOGEN SYNONYM: Pseudomonas cepacia
SOURCE: R. Gitaitis
DISEASE: Witches'-broom
HOST: Alfalfa
Alfalfa plant (center) exhibiting stunting and proliferation of stems. Other symptoms are small, rounded, chlorotic, often puckered leaves and a yellowish cast.

Witches'-broom | Alfalfa
DISEASE: Witches'-broom
HOST: Alfalfa (Medicago sativa)
PATHOGEN: 'Candidatus Phytoplasma trifolii'
PATHOGEN SYNONYM: Phytoplasma Clover proliferation group
SOURCE: S. Thomson
DISEASE: Witches'-broom
HOST: Alfalfa
Young plant (left) with small, numerous stems (witches'-broom). Healthy stems (right).

Witches'-broom | Alfalfa
DISEASE: Witches'-broom
HOST: Alfalfa (Medicago sativa)
PATHOGEN: 'Candidatus Phytoplasma trifolii'
PATHOGEN SYNONYM: Phytoplasma Clover proliferation group
SOURCE: S. Thomson