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: 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 mosaic
HOST: Wheat
Diseased leaves with mosaic pattern exhibiting various amounts of yellowing. Leaves were artificially inoculated by vacuum infiltration.
Bacterial mosaic | Wheat
DISEASE: Bacterial mosaic
HOST: Wheat (Triticum aestivum)
PATHOGEN: Clavibacter michiganensis subsp. tessellarius
SOURCE: A. Vidaver
DISEASE: Bacterial wilt
HOST: Grass
Wilted and dead patches of diseased creeping bent grass (Toronto grass) on golf green.
Bacterial wilt | Grass
DISEASE: Bacterial wilt
HOST: Grass (Agrostis stolonifera)
PATHOGEN: Xanthomonas translucens pv. poae
SOURCE: D. Roberts
DISEASE: Bacterial wilt
HOST: Grass
Irregular disease patterns on golf green. The cultivars Toronto, Cohansey, and Nimisilia are primary hosts of the disease.
Bacterial wilt | Grass
DISEASE: Bacterial wilt
HOST: Grass (Agrostis stolonifera)
PATHOGEN: Xanthomonas translucens pv. poae
SOURCE: D. Roberts
DISEASE: Bacterial wilt
HOST: Squash
Field with severe symptoms of wilt. Foliage often is chlorotic and leaf margins may be chlorotic and necrotic before plant death. Bacterial ooze may be seen streaming from the xylem when infected stems are cut.
Bacterial wilt | Squash
DISEASE: Bacterial wilt
HOST: Squash (Cucurbita maxima)
PATHOGEN: Erwinia tracheiphila
SOURCE: B. Jacobsen, M. Shurtleff
DISEASE: Black chaff (Bacterial leaf streak)
HOST: Wheat
Water-soaked stage of leaf streak.
Black chaff (Bacterial leaf streak) | Wheat
DISEASE: Black chaff (Bacterial leaf streak)
HOST: Wheat (Triticum aestivum)
PATHOGEN: Xanthomonas translucens pv. undulosa
SOURCE: S. Thomson