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: Hibiscus
Hibiscus leaves with large, black spots with chlorosis occurring near some lesions.

Bacterial leaf spot | Hibiscus
DISEASE: Bacterial leaf spot
HOST: Hibiscus (Hibiscus sp.)
PATHOGEN: Xanthomonas campestris pv. esculenti
SOURCE: R. Raabe
DISEASE: Halo blight
HOST: Bean
'Baby Fordhook' with water-soaked leaf lesions without halos. This strain of the pathogen is not systemic on this cultivar.

Halo blight | Bean
DISEASE: Halo blight
HOST: Bean (Phaseolus lunatus 'Baby Fordhook')
PATHOGEN: Pseudomonas syringae pv. phaseolicola
PATHOGEN SYNONYM: Pseudomonas savastanoi pv. phaseolicola
SOURCE: M. Schroth