DISEASE: Aster yellows
HOST: Watercress
Diseased watercress (left) and healthy plant (right).
Aster yellows | Watercress
DISEASE: Aster yellows
HOST: Watercress (Nasturtium officinale)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: W. Borth
DISEASE: Aster yellows
HOST: Wheat
Healthy head (left) and diseased head (right). Diseased seedlings may die within 2 to 3 weeks. Infected heads of surviving plants are small and sterile, with distorted awns.
Aster yellows | Wheat
DISEASE: Aster yellows
HOST: Wheat (Triticum aestivum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: L. N. Chiykowski
DISEASE: Aster yellows
HOST: Zinnia
Yellowing and shoot proliferation of foliage.
Aster yellows | Zinnia
DISEASE: Aster yellows
HOST: Zinnia (Zinnia violacea)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: J. Forsberg, M. Shurtleff
DISEASE: Bacterial stem rot
HOST: Tomato
Stem with long necrotic lesions. The pathogen often enters plants following pruning injuries.
Bacterial stem rot | Tomato
DISEASE: Bacterial stem rot
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: Pectobacterium atrosepticum
PATHOGEN SYNONYM: Ewinia carotovora subsp. atroseptica
SOURCE: A. Alvarez
DISEASE: Bacterial stem rot
HOST: Tomato
Wilt is first symptom of disease. Later, the pith usually disintegrates, causing hollow and blackened stems.
Bacterial stem rot | Tomato
DISEASE: Bacterial stem rot
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: Pectobacterium atrosepticum
PATHOGEN SYNONYM: Erwinia carotovora subsp. atroseptica
SOURCE: M. Stanghelllini
DISEASE: Blackleg
HOST: Potato
Black, elongated necrotic areas, characteristic of stem rot.
Blackleg | Potato
DISEASE: Blackleg
HOST: Potato (Solanum tuberosum)
PATHOGEN: Pectobacterium atrosepticum
PATHOGEN SYNONYM: Erwinia carotovora subsp. atroseptica
SOURCE: S. Mohan
DISEASE: Blackleg
HOST: Potato
Black necrotic stem; late stage of disease.
Blackleg | Potato
DISEASE: Blackleg
HOST: Potato (Solanum tuberosum)
PATHOGEN: Pectobacterium atrosepticum
PATHOGEN SYNONYM: Erwinia carotovora subsp. atroseptica
SOURCE: S. Mohan
DISEASE: Blackleg
HOST: Potato
Infected stem with brown necrotic symptoms.
Blackleg | Potato
DISEASE: Blackleg
HOST: Potato (Solanum tuberosum)
PATHOGEN: Pectobacterium atrosepticum
PATHOGEN SYNONYM: Erwinia carotovora subsp. atroseptica
SOURCE: R. Rowe
DISEASE: Blackleg
HOST: Potato
Stems with severe blackleg symptoms.
Blackleg | Potato
DISEASE: Blackleg
HOST: Potato (Solanum tuberosum)
PATHOGEN: Pectobacterium atrosepticum
PATHOGEN SYNONYM: Erwinia carotovora subsp. atroseptica
SOURCE: A. Paulus, M. Shurtleff