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: Bacterial blight
HOST: Hazelnut
Diseased young tree with discoloration of the cambium. Dieback of young twigs and branches is characteristic. Other typical symptoms are bud and twig necrosis and small, angular or round, water-soaked leaf spots.
Bacterial blight | Hazelnut
DISEASE: Bacterial blight
HOST: Hazelnut (Corylus americana)
PATHOGEN: Xanthomonas arboricola pv. corylina
SOURCE: J. Pscheidt
DISEASE: Bacterial canker
HOST: Hazelnut
Primary symptoms are failure of buds to break and withering and death of new foliage in spring. Dead leaves remain attached to limbs after normal leaf fall.
Bacterial canker | Hazelnut
DISEASE: Bacterial canker
HOST: Hazelnut (Corylus americana)
PATHOGEN: Pseudomonas syringae pv. avellanae
PATHOGEN SYNONYM: Pseudomonas avellanae
SOURCE: P. Psalidas
DISEASE: Bacterial leaf streak
HOST: Millet
Leaf with small, linear, water-soaked, reddish brown stripes.
Bacterial leaf streak | Millet
DISEASE: Bacterial leaf streak
HOST: Millet (Pennisetum glaucum)
PATHOGEN: Xanthomonas campestris pv. pennamericanum
SOURCE: L. Claflin
DISEASE: Bacterial leaf streak
HOST: Millet
Advanced stage of disease.
Bacterial leaf streak | Millet
DISEASE: Bacterial leaf streak
HOST: Millet (Pennisetum glaucum)
PATHOGEN: Xanthomonas campestris pv. pennamericanum
SOURCE: L. Claflin
DISEASE: Bacterial leaf stripe
HOST: Millet
Leaf with long reddish stripes, usually vein delimited.
Bacterial leaf stripe | Millet
DISEASE: Bacterial leaf stripe
HOST: Millet (Pennisetum glaucum)
PATHOGEN: Acidovorax avenae
PATHOGEN SYNONYM: Acidovorax avenae subsp. avenae
SOURCE: L. Claflin
DISEASE: Bacterial leaf stripe
HOST: Millet
Leaf with reddish stripes delimited by veins.
Bacterial leaf stripe | Millet
DISEASE: Bacterial leaf stripe
HOST: Millet (Pennisetum glaucum)
PATHOGEN: Acidovorax avenae
PATHOGEN SYNONYM: Acidovorax avenae subsp. avenae
SOURCE: L. Claflin
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