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: Bougainvillea
Bougainvillea with reddish brown, angular, vein-delimited spots and leaf distortion.

Bacterial leaf spot | Bougainvillea
DISEASE: Bacterial leaf spot
HOST: Bougainvillea (Bougainvillea sp.)
PATHOGEN: Burkholderia andropogonis
PATHOGEN SYNONYM: Pseudomonas andropogonis
SOURCE: A. Hayward
DISEASE: Pear decline
HOST: Pear
'Bartlett' pears were grafted onto tolerant rootstock. All trees are infected. Note yellowish, diseased branches.

Pear decline | Pear
DISEASE: Pear decline
HOST: Pear (Pyrus communis 'Bartlett')
PATHOGEN: 'Candidatus Phytoplasma pyri'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: C. Smart
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