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
HOST: Laurel (California laurel)
Leaf with dark brown, angular spots.

Bacterial leaf spot | Laurel (California laurel)
DISEASE: Bacterial leaf spot
HOST: Laurel (California laurel) (Umbellularia californica)
PATHOGEN: Pseudomonas sp.
PATHOGEN SYNONYM: Pseudomonas lauracearum
SOURCE: W. Sinclair
DISEASE: Halo blight
HOST: Coffee
Leaf with blackish lesions surrounded by yellow halos.

Halo blight | Coffee
DISEASE: Halo blight
HOST: Coffee (Coffea dewevrei)
PATHOGEN: Pseudomonas syringae pv. garcae
SOURCE: S. Mohan
DISEASE: Halo blight
HOST: Coffee
Young blighted coffee plant.

Halo blight | Coffee
DISEASE: Halo blight
HOST: Coffee (Coffea dewevrei)
PATHOGEN: Pseudomonas syringae pv. garcae
SOURCE: S. Mohan
DISEASE: Halo blight
HOST: Coffee
Stem blight stage of disease.

Halo blight | Coffee
DISEASE: Halo blight
HOST: Coffee (Coffea dewevrei)
PATHOGEN: Pseudomonas syringae pv. garcae
SOURCE: S. Mohan
DISEASE: Halo blight
HOST: Coffee
Coffee leaf with lesion on margin.

Halo blight | Coffee
DISEASE: Halo blight
HOST: Coffee (Coffea dewevrei)
PATHOGEN: Pseudomonas syringae pv. garcae
SOURCE: S. Mohan