DISEASE: Aster yellows
HOST: Potato
Chlorotic and stunted foliage with necrotic leaf margins. Other symptoms may be phyllody, virescence, purple or yellow pigmentation, and rolling of leaflets.
![](/sites/default/files/plant_disease/images/0763.jpg)
Aster yellows | Potato
DISEASE: Aster yellows
HOST: Potato (Solanum tuberosum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson
DISEASE: Aster yellows
HOST: Potato
Stunted, chlorotic plants (left) with stiff, rolled leaves.
![](/sites/default/files/plant_disease/images/0764.jpg)
Aster yellows | Potato
DISEASE: Aster yellows
HOST: Potato (Solanum tuberosum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson
DISEASE: Aster yellows
HOST: Potato
Diseased plant with malformed tubers.
![](/sites/default/files/plant_disease/images/0765.jpg)
Aster yellows | Potato
DISEASE: Aster yellows
HOST: Potato (Solanum tuberosum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson
DISEASE: Aster yellows
HOST: Ranunculus
Malformation of diseased flower.
![](/sites/default/files/plant_disease/images/0804.jpg)
Aster yellows | Ranunculus
DISEASE: Aster yellows
HOST: Ranunculus (Ranunculus sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Raabe
DISEASE: Bacterial leaf spot (Blight)
HOST: Ranunculus
Leaf with large, brown necrotic areas delimited by veins.
![](/sites/default/files/plant_disease/images/0805.jpg)
Bacterial leaf spot (Blight) | Ranunculus
DISEASE: Bacterial leaf spot (Blight)
HOST: Ranunculus (Ranunculus sp.)
PATHOGEN: Xanthomonas campestris
SOURCE: R. Raabe
DISEASE: Bacterial ring rot
HOST: Potato
Stunted plant with withered leaves (right).
![](/sites/default/files/plant_disease/images/0766.jpg)
Bacterial ring rot | Potato
DISEASE: Bacterial ring rot
HOST: Potato (Solanum tuberosum)
PATHOGEN: Clavibacter michiganensis subsp. sepedonicus
SOURCE: M. Schroth
DISEASE: Bacterial ring rot
HOST: Potato
Infected leaf with advanced stage of interveinal necrosis.
![](/sites/default/files/plant_disease/images/0767.jpg)
Bacterial ring rot | Potato
DISEASE: Bacterial ring rot
HOST: Potato (Solanum tuberosum)
PATHOGEN: Clavibacter michiganensis subsp. sepedonicus
SOURCE: S. Thomson
DISEASE: Bacterial ring rot
HOST: Potato
Foliage symptoms are upward rolling of leaves and marginal necrosis of lower leaves.
![](/sites/default/files/plant_disease/images/0768.jpg)
Bacterial ring rot | Potato
DISEASE: Bacterial ring rot
HOST: Potato (Solanum tuberosum)
PATHOGEN: Clavibacter michiganensis subsp. sepedonicus
SOURCE: G. Franc