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: 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
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
DISEASE: Pseudomonas leaf spot
HOST: Marigold
Chlorotic leaves with total loss of chlorophyll. Disease is also known as toxic chlorosis.

Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin
DISEASE: Pseudomonas leaf spot
HOST: Primrose
Leaf with brownish red spots and reddening of adjacent areas. Disease begins as small, water-soaked lesions that later coalesce into large necrotic spots.

Pseudomonas leaf spot | Primrose
DISEASE: Pseudomonas leaf spot
HOST: Primrose (Primula sp.)
PATHOGEN: Pseudomonas syringae pv. primulae
SOURCE: APS