DISEASE: Aster yellows
HOST: Marigold
Infected plant (left) with yellowing and stunting.

Aster yellows | Marigold
DISEASE: Aster yellows
HOST: Marigold (Tagetes erecta)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: M. Shurtleff
DISEASE: Bacterial leaf spot
HOST: Magnolia
Leaf with black, angular spots.

Bacterial leaf spot | Magnolia
DISEASE: Bacterial leaf spot
HOST: Magnolia (Magnolia soulangiana)
PATHOGEN: Pseudomonas cichorii
SOURCE: R. Raabe
DISEASE: Halo blight
HOST: Yam bean
Leaves with necrotic lesions surrounded by yellow halos.

Halo blight | Yam bean
DISEASE: Halo blight
HOST: Yam bean (Pachyrhizus erosus)
PATHOGEN: Pseudomonas syringae pv. phaseolicola
PATHOGEN SYNONYM: Pseudomonas savastanoi pv. phaseolicola
SOURCE: L. Fucikovsky
DISEASE: Pseudomonas leaf spot
HOST: Marigold
Marigolds with yellow apical chlorosis attributed to toxin production by the pathogen.

Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin