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: Strawberry lethal decline
HOST: Strawberry
Diseased plant with bronzing of older leaves and upward rolling or cupping of younger leaves. Leaves are chlorotic on upper surfaces and reddish or purplish on lower surfaces. In time, the entire plant dies.

Strawberry lethal decline | Strawberry
DISEASE: Strawberry lethal decline
HOST: Strawberry (Fragaria × ananassa)
PATHOGEN: 'Candidatus Phytoplasma' sp.
PATHOGEN SYNONYM: Phytoplasma (undefined)
SOURCE: H. Schwartz
DISEASE: X-disease (Western X) or buckskin
HOST: Cherry
Comparison of normal, dark cherries (in hand) with infected, immature cherries with less pigmentation.

X-disease (Western X) or buckskin | Cherry
DISEASE: X-disease (Western X) or buckskin
HOST: Cherry (Prunus avium)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: A. Purcell, M. Davis
DISEASE: X-disease (Western X) or buckskin
HOST: Cherry
Healthy cherry shoot (left) and stunted shoot (right).

X-disease (Western X) or buckskin | Cherry
DISEASE: X-disease (Western X) or buckskin
HOST: Cherry (Prunus avium)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: S. Thomson
DISEASE: X-disease (Western X) or buckskin
HOST: Cherry
Infected trees on 'Mazzard' rootstock (right) may live for years, producing fruit with symptoms. Trees on 'Mahaleb' rootstock (left) usually die rapidly in year of infection, about time of fruit ripening.

X-disease (Western X) or buckskin | Cherry
DISEASE: X-disease (Western X) or buckskin
HOST: Cherry (Prunus avium)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: S. Thomson
DISEASE: X-disease (Western X) or buckskin
HOST: Cherry
X-disease causes undersized, yellowish fruit. Diseased branches turn rusty red near end of season. Some defoliation occurs on diseased branches.

X-disease (Western X) or buckskin | Cherry
DISEASE: X-disease (Western X) or buckskin
HOST: Cherry (Prunus cerasus)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: A. Jones