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: Australian citrus dieback
HOST: Citrus (Grapefruit)
Leaves with mottled chlorosis.

Australian citrus dieback | Citrus (Grapefruit)
DISEASE: Australian citrus dieback
HOST: Citrus (Grapefruit) (Citrus paradisi)
PATHOGEN: 'Candidatus Phytoplasma' sp.
PATHOGEN SYNONYM: Phytoplasma (undefined)
SOURCE: P. Broadbent
DISEASE: Australian citrus dieback
HOST: Citrus (Grapefruit)
Late stage of disease. Note yellowing of leaf veins and entire leaves.

Australian citrus dieback | Citrus (Grapefruit)
DISEASE: Australian citrus dieback
HOST: Citrus (Grapefruit) (Citrus paradisi)
PATHOGEN: 'Candidatus Phytoplasma' sp.
PATHOGEN SYNONYM: Phytoplasma (undefined)
SOURCE: P. Broadbent
DISEASE: Bacterial leaf streak
HOST: Ti
Leaf with reddish brown streaks.

Bacterial leaf streak | Ti
DISEASE: Bacterial leaf streak
HOST: Ti (Cordyline fruticosa)
PATHOGEN: Xanthomonas axonopodis pv. dieffenbachiae
PATHOGEN SYNONYM: Xanthomonas campestris pv. dieffenbachiae
SOURCE: R. Raabe
DISEASE: Bacterial leaf streak
HOST: Ti
Leaf with reddish brown necrotic streaks, late stage of disease.

Bacterial leaf streak | Ti
DISEASE: Bacterial leaf streak
HOST: Ti (Cordyline terminalis)
PATHOGEN: Xanthomonas axonopodis pv. dieffenbachiae
PATHOGEN SYNONYM: Xanthomonas campestris pv. dieffenbachiae
SOURCE: A. Alvarez
DISEASE: Bacterial leaf streak
HOST: Ti
Leaves of two different ti cultivars with water-soaked and necrotic streaks.

Bacterial leaf streak | Ti
DISEASE: Bacterial leaf streak
HOST: Ti (Cordyline terminalis)
PATHOGEN: Xanthomonas axonopodis pv. dieffenbachiae
PATHOGEN SYNONYM: Xanthomonas campestris pv. dieffenbachiae
SOURCE: R. Raabe
DISEASE: Citrus canker
HOST: Citrus (Grapefruit)
Grapefruit with corky, raised lesions.

Citrus canker | Citrus (Grapefruit)
DISEASE: Citrus canker
HOST: Citrus (Grapefruit) (Citrus paradisi)
PATHOGEN: Xanthomonas citri subsp. citri
PATHOGEN SYNONYM: Xanthomonas citri
SOURCE: T. Gottwald
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