DISEASE: Brittle root
HOST: Horseradish
Dying, stunted, yellow to brown horseradish plants.

Brittle root | Horseradish
DISEASE: Brittle root
HOST: Horseradish (Armoracia rusticana)
PATHOGEN: Spiroplasma citri
SOURCE: C. Eastman, M. Davis
DISEASE: Brittle root
HOST: Horseradish
Close-up of stunted, yellow horseradish plants.

Brittle root | Horseradish
DISEASE: Brittle root
HOST: Horseradish (Armoracia rusticana)
PATHOGEN: Spiroplasma citri
SOURCE: D. Sherrod
DISEASE: Brittle root
HOST: Horseradish
Horseradish with discolored internal tissues. Healthy root segment (top right).

Brittle root | Horseradish
DISEASE: Brittle root
HOST: Horseradish (Armoracia rusticana)
PATHOGEN: Spiroplasma citri
SOURCE: J. Fletcher, M. Davis
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato
Wilted, stunted plants with yellowing foliage.

Brown rot (Bacteral wilt) | Potato
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato (Solanum tuberosum)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: D. P. Weingartner
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato
External symptoms of the disease.

Brown rot (Bacteral wilt) | Potato
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato (Solanum tuberosum)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: D. Thurston
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato
Tubers with distinct grayish brown rings and bacterial ooze from vascular tissues.

Brown rot (Bacteral wilt) | Potato
DISEASE: Brown rot (Bacteral wilt)
HOST: Potato (Solanum tuberosum)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: A. Hayward
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