DISEASE: Angular leaf spot
HOST: Tobacco
Leaf with light brown, angular spots. The difference between this disease and wildfire of tobacco is that wildfire is caused by a strain that produces tabtoxin. It causes conspicuous halos around lesions and large parts of a leaf may turn yellow .
Angular leaf spot | Tobacco
DISEASE: Angular leaf spot
HOST: Tobacco (Nicotiana tabacum)
PATHOGEN: Pseudomonas syringae pv. tabaci
SOURCE: H. Shew
DISEASE: Angular leaf spot
HOST: Tobacco
Yellowing of adjacent tissues occur as spots age (midseason). It causes conspicuous halos around lesions. Large parts of a leaf may turn yellow.
Angular leaf spot | Tobacco
DISEASE: Angular leaf spot
HOST: Tobacco (Nicotiana tabacum)
PATHOGEN: Pseudomonas syringae pv. tabaci
SOURCE: H. Shew
DISEASE: Angular leaf spot
HOST: Tobacco
Severely diseased leaf with extensive yellowing.
Angular leaf spot | Tobacco
DISEASE: Angular leaf spot
HOST: Tobacco (Nicotiana tabacum)
PATHOGEN: Pseudomonas syringae pv. tabaci
SOURCE: H. Shew
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: 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 fasciation (Leafy gall)
HOST: Tobacco
Bacterial fasciation of tobacco.
Bacterial fasciation (Leafy gall) | Tobacco
DISEASE: Bacterial fasciation (Leafy gall)
HOST: Tobacco (Nicotiana tabacum)
PATHOGEN: Rhodococcus fascians
SOURCE: R. Raabe
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