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: Slime flux
HOST: Elm
Although bacteria are associated with slime fluxes of many trees, the causal agents have not been identified.

Slime flux | Elm
DISEASE: Slime flux
HOST: Elm (Ulmus pumila)
PATHOGEN: Causal agent unknown
SOURCE: W. Sinclair