DISEASE: Bacterial blight (Boll rot)
HOST: Cotton
Boll rot first appears as raised, water-soaked lesions, which become sunken and turn brown to black with time.

Bacterial blight (Boll rot) | Cotton
DISEASE: Bacterial blight (Boll rot)
HOST: Cotton (Gossypium barbadense)
PATHOGEN: Xanthomonas citri subsp. malvacearum
PATHOGEN SYNONYM: Xanthomonas campestris pv. malvacearum
SOURCE: A. Hayward
DISEASE: Bacterial blight (Boll rot)
HOST: Cotton
Infection of bolls causes premature opening and increased susceptibility to secondary, saprophytic microorganisms that cause rot. Note discolored cotton.

Bacterial blight (Boll rot) | Cotton
DISEASE: Bacterial blight (Boll rot)
HOST: Cotton (Gossypium barbadense)
PATHOGEN: Xanthomonas citri subsp. malvacearum
PATHOGEN SYNONYM: Xanthomonas campestris pv. malvacearum
SOURCE: APS
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: Maize bushy stunt
HOST: Corn (Maize)
Maize with chlorotic leaf margins and reddening of tips and margins of older leaves.

Maize bushy stunt | Corn (Maize)
DISEASE: Maize bushy stunt
HOST: Corn (Maize) (Zea mays)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: L. Nault, M. Davis
DISEASE: Maize bushy stunt
HOST: Corn (Maize)
Late stage of disease.

Maize bushy stunt | Corn (Maize)
DISEASE: Maize bushy stunt
HOST: Corn (Maize) (Zea mays)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Davis, M. Davis
DISEASE: Maize bushy stunt
HOST: Corn (Maize)
Dalbulus maidis, leafhopper vector of 'Candidatus Phytoplasma asteris', the cause of maize bushy stunt.

Maize bushy stunt | Corn (Maize)
DISEASE: Maize bushy stunt
HOST: Corn (Maize) (Zea mays)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: L. Nault, M. Davis