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: Rhododendron
Leaf with light brown, irregularly shaped spots.

Bacterial leaf spot | Rhododendron
DISEASE: Bacterial leaf spot
HOST: Rhododendron (Rhododendron catawbiense 'Album')
PATHOGEN: Pseudomonas cichorii
SOURCE: W. Uddin, W. Sinclair
DISEASE: Bacterial leaf spot
HOST: Turnip
Leaf with many tan, dry-appearing, angular spots.

Bacterial leaf spot | Turnip
DISEASE: Bacterial leaf spot
HOST: Turnip (Brassica rapa)
PATHOGEN: Xanthomonas campestris pv. armoraciae
SOURCE: R. Campbell