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 leaf spot (Head rot)
HOST: Cauliflower
Leaves with tiny lesions surrounded by large halos.
Bacterial leaf spot (Head rot) | Cauliflower
DISEASE: Bacterial leaf spot (Head rot)
HOST: Cauliflower (Brassica oleracea var. botrytis)
PATHOGEN: Pseudomonas syringae pv. maculicola
SOURCE: R. Campbell
DISEASE: Bacterial leaf spot (Head rot)
HOST: Cauliflower
Section of a cauliflower head with discolored, infected tissues.
Bacterial leaf spot (Head rot) | Cauliflower
DISEASE: Bacterial leaf spot (Head rot)
HOST: Cauliflower (Brassica oleracea var. botrytis)
PATHOGEN: Pseudomonas syringae pv. maculicola
SOURCE: R. Campbell
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 rot
HOST: Cauliflower
Brown, necrotic, rotted areas on flower parts and typical V-shaped necrotic areas on leaf margins.
Black rot | Cauliflower
DISEASE: Black rot
HOST: Cauliflower (Brassica oleracea var. botrytis)
PATHOGEN: Xanthomonas campestris pv. campestris
SOURCE: B. Jacobsen, M. Shurtleff
DISEASE: Oleander knot
HOST: Oleander
Oleander with small knots/galls on leaf and stems.
Oleander knot | Oleander
DISEASE: Oleander knot
HOST: Oleander (Nerium oleander)
PATHOGEN: Pseudomonas savastanoi pv. nerii
SOURCE: W. Sinclair
DISEASE: Oleander knot
HOST: Oleander
Young stem with knots/galls.
Oleander knot | Oleander
DISEASE: Oleander knot
HOST: Oleander (Nerium oleander)
PATHOGEN: Pseudomonas savastanoi pv. nerii
SOURCE: R. Raabe
DISEASE: Oleander knot
HOST: Oleander
Leaf with early stage of knot/gall formation.
Oleander knot | Oleander
DISEASE: Oleander knot
HOST: Oleander (Nerium oleander)
PATHOGEN: Pseudomonas savastanoi pv. nerii
SOURCE: R. Raabe
DISEASE: Oleander knot
HOST: Oleander
Infected flowers with small knots/galls and necroses.
Oleander knot | Oleander
DISEASE: Oleander knot
HOST: Oleander (Nerium oleander)
PATHOGEN: Pseudomonas savastanoi pv. nerii
SOURCE: W. Sinclair