DISEASE: Aster yellows
HOST: Barley
Infection by this phytoplasm causes twisted awns and sterile florets.

Aster yellows | Barley
DISEASE: Aster yellows
HOST: Barley (Hordeum vulgare)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: E. Banttari
DISEASE: Aster yellows
HOST: Barley
Small necrotic spots on lower leaves and red coalescing streaks on upper leaves.

Aster yellows | Barley
DISEASE: Aster yellows
HOST: Barley (Hordeum vulgare)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: E. Banttari
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.

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.

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.

Aster yellows | Potato
DISEASE: Aster yellows
HOST: Potato (Solanum tuberosum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson
DISEASE: Bacterial blight
HOST: Bean
Bean leaves with large necrotic areas.

Bacterial blight | Bean
DISEASE: Bacterial blight
HOST: Bean (Phaseolus vulgaris)
PATHOGEN: Xanthomonas axonopodis pv. phaseoli
PATHOGEN SYNONYM: Xanthomonas campestris pv. phaseoli
SOURCE: J. Young
DISEASE: Bacterial blight
HOST: Bean
Field of severely diseased beans.

Bacterial blight | Bean
DISEASE: Bacterial blight
HOST: Bean (Phaseolus vulgaris)
PATHOGEN: Xanthomonas axonopodis pv. phaseoli
PATHOGEN SYNONYM: Xanthomonas campestris pv. phaseoli
SOURCE: M. Shurtleff
DISEASE: Bacterial blight
HOST: Bean
Close-up of necrotic leaf lesions.

Bacterial blight | Bean
DISEASE: Bacterial blight
HOST: Bean (Phaseolus vulgaris)
PATHOGEN: Xanthomonas axonopodis pv. phaseoli
PATHOGEN SYNONYM: Xanthomonas campestris pv. phaseoli
SOURCE: A. Alvarez
DISEASE: Bacterial blight
HOST: Bean
Bean leaflet with large necrotic lesions surrounded by chlorotic zones.

Bacterial blight | Bean
DISEASE: Bacterial blight
HOST: Bean (Phaseolus vulgaris)
PATHOGEN: Xanthomonas axonopodis pv. phaseoli
PATHOGEN SYNONYM: Xanthomonas campestris pv. phaseoli
SOURCE: I. Hubbeling, J. van der Wolf