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: Aster yellows
HOST: Squash
Diagnostic characteristics for the disease are yellowing of young leaves, proliferation of secondary shoots, and rigid erect habit. Leaves are misshapen and smaller than normal and have stiff, thick laminae.

Aster yellows | Squash
DISEASE: Aster yellows
HOST: Squash (Cucurbita sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Miller
DISEASE: Lethal decline
HOST: Palm
Date palm exhibiting symptoms of lethal decline.

Lethal decline | Palm
DISEASE: Lethal decline
HOST: Palm (Phoenix dactylifera)
PATHOGEN: 'Candidatus Phytoplasma palmae'
PATHOGEN SYNONYM: Phytoplasma Coconut lethal yellowing group
SOURCE: W. Sinclair
DISEASE: Lethal decline
HOST: Palm
Date palm with late stage of lethal decline.

Lethal decline | Palm
DISEASE: Lethal decline
HOST: Palm (Phoenix dactylifera)
PATHOGEN: 'Candidatus Phytoplasma palmae'
PATHOGEN SYNONYM: Phytoplasma Coconut lethal yellowing group
SOURCE: W. Sinclair
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