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: Pith necrosis
HOST: Geranium
Geranium with wilted, yellow necrotic leaves.
Pith necrosis | Geranium
DISEASE: Pith necrosis
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Pseudomonas corrugata
SOURCE: A. Magyarosy, D. Thomas
DISEASE: Pith necrosis
HOST: Geranium
Pitted and hollow stems, one of the disease symptoms.
Pith necrosis | Geranium
DISEASE: Pith necrosis
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Pseudomonas corrugata
SOURCE: A. Magyarosy, D. Thomas
DISEASE: Pith necrosis
HOST: Geranium
Discolored stem caused by systemic infection of the pathogen.
Pith necrosis | Geranium
DISEASE: Pith necrosis
HOST: Geranium (Pelargonium sp.)
PATHOGEN: Pseudomonas corrugata
SOURCE: A. Magyarosy, D. Thomas
DISEASE: Pith necrosis
HOST: Tomato
Cracked, dry, hollow stems with internal necrosis.
Pith necrosis | Tomato
DISEASE: Pith necrosis
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: Pseudomonas corrugata
SOURCE: A. Alvarez
DISEASE: Pith necrosis
HOST: Tomato
External necrotic stem tissues. Initial symptoms include chlorosis of young leaves. Wilting may occur when disease is severe.
Pith necrosis | Tomato
DISEASE: Pith necrosis
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: Pseudomonas corrugata
SOURCE: K. Natsuaki, M. Goto