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: Foamy canker
HOST: Koa
Foamy canker of koa is associated with bacteria and yeast. The causal agent has not been identified.
Foamy canker | Koa
DISEASE: Foamy canker
HOST: Koa (Acacia koa)
PATHOGEN: Causal agent unknown
SOURCE: H. Keyser
DISEASE: Foamy canker
HOST: Koa
Dieback of koa tree. The causal agent has not been identified.
Foamy canker | Koa
DISEASE: Foamy canker
HOST: Koa (Acacia koa)
PATHOGEN: Causal agent unknown
SOURCE: H. Keyser