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: Aster
Foliar symptoms of chlorosis, malformation of leaves, and phyllody.
Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. McCoy, M. Davis
DISEASE: Aster yellows
HOST: Aster
Flowers with phyllody (left and center). Healthy flower (right).
Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. McCoy, M. Davis
DISEASE: Aster yellows
HOST: Aster
Macrosteles sp., a leafhopper vector of aster yellows phytoplasma.
Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: J. Clark, A. Purcell, M. Davis
DISEASE: Bacterial blight (Bacterial necrosis)
HOST: Grape
Stem necrosis of grape.
Bacterial blight (Bacterial necrosis) | Grape
DISEASE: Bacterial blight (Bacterial necrosis)
HOST: Grape (Vitis vinifera)
PATHOGEN: Xylophilus ampelinus
PATHOGEN SYNONYM: Xanthomonas ampelina
SOURCE: N. Schaad
DISEASE: Bacterial blight (Bacterial necrosis)
HOST: Grape
Stem with cankers and discolored external tissues.
Bacterial blight (Bacterial necrosis) | Grape
DISEASE: Bacterial blight (Bacterial necrosis)
HOST: Grape (Vitis vinifera)
PATHOGEN: Xylophilus ampelinus
PATHOGEN SYNONYM: Xanthomonas ampelina
SOURCE: N. Schaad
DISEASE: Bacterial blight (Bacterial necrosis)
HOST: Grape
Severe infection in vineyard is noted by dead canes. Symptoms are most severe in spring; shoot blight, occasional spots on leaves, and cankers are common.
Bacterial blight (Bacterial necrosis) | Grape
DISEASE: Bacterial blight (Bacterial necrosis)
HOST: Grape (Vitis vinifera)
PATHOGEN: Xylophilus ampelinus
PATHOGEN SYNONYM: Xanthomonas ampelina
SOURCE: C. Manceau, N. Schaad