DISEASE: Aster yellows
HOST: Wheat
Healthy head (left) and diseased head (right). Diseased seedlings may die within 2 to 3 weeks. Infected heads of surviving plants are small and sterile, with distorted awns.

Aster yellows | Wheat
DISEASE: Aster yellows
HOST: Wheat (Triticum aestivum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: L. N. Chiykowski
DISEASE: Australian citrus dieback
HOST: Citrus (Lime)
Severe decline, a late stage of disease. The disease spreads slowly in mature trees, progressing faster in young trees.

Australian citrus dieback | Citrus (Lime)
DISEASE: Australian citrus dieback
HOST: Citrus (Lime) (Citrus sp.)
PATHOGEN: 'Candidatus Phytoplasma australiense'
PATHOGEN SYNONYM: Phytoplasma Stolbur group
SOURCE: P. Broadbent
DISEASE: Bacterial blast and black pit
HOST: Citrus (Lime)
Characteristic symptoms of brownish black lesions on twigs and leaves (blast), starting with infection of petioles. Black pit refers to brown to black sunken spots on fruit, 5 to 20 mm in diameter.

Bacterial blast and black pit | Citrus (Lime)
DISEASE: Bacterial blast and black pit
HOST: Citrus (Lime) (Citrus sp.)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: P. Broadbent
DISEASE: Bacterial leaf blight
HOST: Wheat
Diseased leaves with whitish blotches. Initial water-soaked spots become necrotic and progress from gray-green to tannish white.

Bacterial leaf blight | Wheat
DISEASE: Bacterial leaf blight
HOST: Wheat (Triticum aestivum)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: J. Otta
DISEASE: Bacterial leaf blight
HOST: Wheat
Diseased leaves with whitish blotches. The disease begins as water-soaked spots and then become necrotic and progresses from gray-green to tannish white.

Bacterial leaf blight | Wheat
DISEASE: Bacterial leaf blight
HOST: Wheat (Triticum aestivum)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: L. Claflin
DISEASE: Bacterial leaf blight
HOST: Wheat
Leaves with reddish tan necrotic lesions.

Bacterial leaf blight | Wheat
DISEASE: Bacterial leaf blight
HOST: Wheat (Triticum aestivum)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: L. Claflin
DISEASE: Bacterial leaf spot (Blight)
HOST: Beet
Seedling blight stage of the disease.

Bacterial leaf spot (Blight) | Beet
DISEASE: Bacterial leaf spot (Blight)
HOST: Beet (Beta vulgaris)
PATHOGEN: Pseudomonas syringae pv. aptata
PATHOGEN SYNONYM: Pseudomonas aptata
SOURCE: C. Schneider
DISEASE: Bacterial leaf spot (Blight)
HOST: Beet
Leaves with dark brown necrotic regions and streaks; two petioles also are infected.

Bacterial leaf spot (Blight) | Beet
DISEASE: Bacterial leaf spot (Blight)
HOST: Beet (Beta vulgaris)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: C. Schneider
DISEASE: Bacterial leaf spot of beet
HOST: Beet
Beet leaves with spots and marginal necrosis.

Bacterial leaf spot of beet | Beet
DISEASE: Bacterial leaf spot of beet
HOST: Beet (Beta vulgaris subsp. vulgaris)
PATHOGEN: Pseudomonas syringae pv. aptata
PATHOGEN SYNONYM: Pseudomonas aptata
SOURCE: P. Brown