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: Carrot yellows
HOST: Carrot
Flowers with shoot proliferation (witches’-broom) (left). Healthy flower (right). Virescence and phyllody of flower parts are common.
Carrot yellows | Carrot
DISEASE: Carrot yellows
HOST: Carrot (Daucus carota)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: M. Schroth
DISEASE: Carrot yellows
HOST: Carrot
Carrot with proliferation of roots. Initial symptoms include yellowing and narrowing of veins of young leaves. The entire leaf later becomes necrotic.
Carrot yellows | Carrot
DISEASE: Carrot yellows
HOST: Carrot (Daucus carota)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: G. S. Abawi
DISEASE: Stewart's wilt
HOST: Corn (Maize)
Wilted seedlings resulting from systemic invasion.
Stewart's wilt | Corn (Maize)
DISEASE: Stewart's wilt
HOST: Corn (Maize) (Zea mays)
PATHOGEN: Pantoea stewartii subsp. stewartii
PATHOGEN SYNONYM: Erwinia stewartii
SOURCE: D. White
DISEASE: Stewart's wilt
HOST: Corn (Maize)
Leaf blight is the dominant symptom of this disease. Lesions begin as gray-green to yellow in color and turn brown in time.
Stewart's wilt | Corn (Maize)
DISEASE: Stewart's wilt
HOST: Corn (Maize) (Zea mays)
PATHOGEN: Pantoea stewartii subsp. stewartii
PATHOGEN SYNONYM: Erwinia stewartii
SOURCE: D. White
DISEASE: Stewart's wilt
HOST: Corn (Maize)
Flea beetle and scars caused by feeding damage. The beetle is a vector and is an overwintering site for the bacterium.
Stewart's wilt | Corn (Maize)
DISEASE: Stewart's wilt
HOST: Corn (Maize) (Zea mays)
PATHOGEN: Pantoea stewartii subsp. stewartii
PATHOGEN SYNONYM: Erwinia stewartii
SOURCE: D. White
DISEASE: Stewart's wilt
HOST: Corn (Maize)
Young wilted plant with pale green and yellow streaks on leaves.
Stewart's wilt | Corn (Maize)
DISEASE: Stewart's wilt
HOST: Corn (Maize) (Zea mays)
PATHOGEN: Pantoea stewartii subsp. stewartii
PATHOGEN SYNONYM: Erwinia stewartii
SOURCE: D. White