DISEASE: Aster yellows
HOST: Chrysanthemum
Stunted diseased plant with small distorted flowers.
Aster yellows | Chrysanthemum
DISEASE: Aster yellows
HOST: Chrysanthemum (Chrysanthemum morifolium)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: B. Raju, M. Davis
DISEASE: Bacterial fasciation (Leafy gall)
HOST: Chrysanthemum
Fasciation of chrysanthemum.
Bacterial fasciation (Leafy gall) | Chrysanthemum
DISEASE: Bacterial fasciation (Leafy gall)
HOST: Chrysanthemum (Chrysanthemum morifolium)
PATHOGEN: Rhodococcus fascians
SOURCE: M. Schroth
DISEASE: Bacterial fasciation (Leafy gall)
HOST: Dahlia
Dalhlia tubers with proliferation and leaf development.
Bacterial fasciation (Leafy gall) | Dahlia
DISEASE: Bacterial fasciation (Leafy gall)
HOST: Dahlia (Dahlia sp.)
PATHOGEN: Rhodococcus fascians
SOURCE: M. Shurtleff
DISEASE: Bacterial fasciation (Leafy gall)
HOST: Dahlia
Bacterial fasciation of dahlia tubers.
Bacterial fasciation (Leafy gall) | Dahlia
DISEASE: Bacterial fasciation (Leafy gall)
HOST: Dahlia (Dahlia sp.)
PATHOGEN: Rhodococcus fascians
SOURCE: H. van Hoof, M. Geesteranus
DISEASE: Bacterial rot
HOST: Dahlia
Longitudinal section of dahlia with discolored, rotted tissues.
Bacterial rot | Dahlia
DISEASE: Bacterial rot
HOST: Dahlia (Dahlia sp.)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: J. Young
DISEASE: Bacterial wilt and blight
HOST: Chrysanthemum
Plants with characteristic symptoms of wilt.
Bacterial wilt and blight | Chrysanthemum
DISEASE: Bacterial wilt and blight
HOST: Chrysanthemum (Chrysanthemum morifolium)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: A. Alvarez
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: Crown gall
HOST: Chrysanthemum
Galls on chrysanthemum stem.
Crown gall | Chrysanthemum
DISEASE: Crown gall
HOST: Chrysanthemum (Chrysanthemum morifolium)
PATHOGEN: Agrobacterium tumefaciens
PATHOGEN SYNONYM: Rhizobium sp.
SOURCE: K. Ohta, M. Goto
DISEASE: Crown gall
HOST: Dahlia
Crown gall of dahlia tubers. Note brownish, rough-surfaced galls, one of which shows rot. Galls often are infected by microorganisms that cause rot.
Crown gall | Dahlia
DISEASE: Crown gall
HOST: Dahlia (Dahlia sp.)
PATHOGEN: Agrobacterium tumefaciens
PATHOGEN SYNONYM: Rhizobium sp.
SOURCE: M. Shurtleff