DISEASE: Aster yellows
HOST: Aster
Foliar symptoms of chlorosis, malformation of leaves, and phyllody.

Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. McCoy, M. Davis
DISEASE: Aster yellows
HOST: Aster
Flowers with phyllody (left and center). Healthy flower (right).

Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. McCoy, M. Davis
DISEASE: Aster yellows
HOST: Aster
Macrosteles sp., a leafhopper vector of aster yellows phytoplasma.

Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: J. Clark, A. Purcell, M. Davis
DISEASE: Bacterial black leaf spot
HOST: Clover
White clover with brown necrotic spots.

Bacterial black leaf spot | Clover
DISEASE: Bacterial black leaf spot
HOST: Clover (Trifolium repens)
PATHOGEN: Burkholderia andropogonis
PATHOGEN SYNONYM: Pseudomonas andropogonis
SOURCE: M. Goto
DISEASE: Bacterial black leaf spot
HOST: Clover
White clover leaves with brownish spots and some yellowing occurring at the margins.

Bacterial black leaf spot | Clover
DISEASE: Bacterial black leaf spot
HOST: Clover (Trifolium repens)
PATHOGEN: Burkholderia andropogonis
PATHOGEN SYNONYM: Pseudomonas andropogonis
SOURCE: R. Gitaitis
DISEASE: Bacterial leaf spot (Canker)
HOST: Ginkgo
Ginkgo leaf with dark brown, elongated necrotic spots.

Bacterial leaf spot (Canker) | Ginkgo
DISEASE: Bacterial leaf spot (Canker)
HOST: Ginkgo (Ginkgo biloba)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: A. Bishop
DISEASE: Bacterial leaf spot (Canker)
HOST: Ginkgo
Ginkgo with leaf spots and canker on stem.

Bacterial leaf spot (Canker) | Ginkgo
DISEASE: Bacterial leaf spot (Canker)
HOST: Ginkgo (Ginkgo biloba)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: A. Bishop
DISEASE: Rugose leaf curl
HOST: Clover
Two rugose, distorted white clover leaves and a healthy leaf. Rugose leaf curl is caused by an unidentified phloem-infecting bacterium.

Rugose leaf curl | Clover
DISEASE: Rugose leaf curl
HOST: Clover (Trifolium repens)
PATHOGEN: Phloem-infecting bacterium
SOURCE: D. Teakle