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: 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: Bacterial leaf spot
HOST: Collard
Leaf with several kinds of spots. Small necrotic lesions with yellow halos, brown lesions, and large, brown necrotic areas caused by coalescing of lesions.

Bacterial leaf spot | Collard
DISEASE: Bacterial leaf spot
HOST: Collard (Brassica oleracea var. acephala)
PATHOGEN: Pseudomonas syringae pv. maculicola
SOURCE: S. Miller