DISEASE: Aster yellows
HOST: Daisy
Daisy with stunted and malformed flowers.
![](/sites/default/files/plant_disease/images/0362.jpg)
Aster yellows | Daisy
DISEASE: Aster yellows
HOST: Daisy (Euryops speciosissimus)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Raabe
DISEASE: Bacterial fasciation (Leafy gall)
HOST: Dahlia
Dalhlia tubers with proliferation and leaf development.
![](/sites/default/files/plant_disease/images/0360.jpg)
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.
![](/sites/default/files/plant_disease/images/0361.jpg)
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.
![](/sites/default/files/plant_disease/images/0359.jpg)
Bacterial rot | Dahlia
DISEASE: Bacterial rot
HOST: Dahlia (Dahlia sp.)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: J. Young
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.
![](/sites/default/files/plant_disease/images/0358.jpg)
Crown gall | Dahlia
DISEASE: Crown gall
HOST: Dahlia (Dahlia sp.)
PATHOGEN: Agrobacterium tumefaciens
PATHOGEN SYNONYM: Rhizobium sp.
SOURCE: M. Shurtleff