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 seedling blight
HOST: Rice
Brown, desiccated seedlings in nursery exhibiting basal chlorosis and withering of second and third leaves.

Bacterial seedling blight | Rice
DISEASE: Bacterial seedling blight
HOST: Rice (Oryza sativa)
PATHOGEN: Burkholderia plantarii
PATHOGEN SYNONYM: Pseudomonas plantarii
SOURCE: H. Honma, M. Goto
DISEASE: Bacterial seedling blight
HOST: Rice
Dead seedlings in half of nursery tray. Symptoms are basal chlorosis and withering of second and third leaves. Infected seedlings become reddish brown and desiccated in time.

Bacterial seedling blight | Rice
DISEASE: Bacterial seedling blight
HOST: Rice (Oryza sativa)
PATHOGEN: Burkholderia plantarii
PATHOGEN SYNONYM: Pseudomonas plantarii
SOURCE: K. Azegami, M. Goto
DISEASE: Bacterial seedling blight
HOST: Rice
Basal chlorosis and withering of second and third leaves. Seedlings become reddish brown with a dry appearance over time. Root growth is retarded and seedlings easily lodge.

Bacterial seedling blight | Rice
DISEASE: Bacterial seedling blight
HOST: Rice (Oryza sativa)
PATHOGEN: Burkholderia plantarii
PATHOGEN SYNONYM: Pseudomonas plantarii
SOURCE: K. Azegami
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