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: Larkspur virescence
HOST: Larkspur
Two diseased plants with stunted and small leaves, lack of flower coloration, and bunched flower buds. Healthy plant (left).

Larkspur virescence | Larkspur
DISEASE: Larkspur virescence
HOST: Larkspur (Delphinium sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Raabe
DISEASE: Ratoon stunt
HOST: Sugarcane
Necrotic, reddish vascular bundles in node of sliced stalk, a diagnostic symptom.

Ratoon stunt | Sugarcane
DISEASE: Ratoon stunt
HOST: Sugarcane (Saccharum officinarum)
PATHOGEN: Leifsonia xyli subsp. xyli
SOURCE: D. Teakle
DISEASE: Ratoon stunt
HOST: Sugarcane
Disease of susceptible cultivar L62-96 (right). External symptoms are characterized by stunting and poor growth.

Ratoon stunt | Sugarcane
DISEASE: Ratoon stunt
HOST: Sugarcane (Saccharum officinarum)
PATHOGEN: Leifsonia xyli subsp. xyli
SOURCE: A. Gillaspie, M. Davis
DISEASE: Ratoon stunt
HOST: Sugarcane
Red discoloration just below nodal tissues is a symptom in mature stalks of 'L41-233'.

Ratoon stunt | Sugarcane
DISEASE: Ratoon stunt
HOST: Sugarcane (Saccharum officinarum)
PATHOGEN: Leifsonia xyli subsp. xyli
SOURCE: A. Gillaspie, M. Davis