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: Cassava
Leaf with angular, water-soaked, vein-delimited lesions.
Bacterial blight | Cassava
DISEASE: Bacterial blight
HOST: Cassava (Manihot esculenta)
PATHOGEN: Xanthomonas axonopodis pv. manihotis
PATHOGEN SYNONYM: Xanthomonas campestris pv. manihotis
SOURCE: A. Hayward
DISEASE: Bacterial blight
HOST: Cassava
Cassava with angular leaf spots and yellow ooze. Symptoms include leaf spots, wilt, and dieback. The bacterium frequently invades systemically.
Bacterial blight | Cassava
DISEASE: Bacterial blight
HOST: Cassava (Manihot esculenta)
PATHOGEN: Xanthomonas axonopodis pv. manihotis
PATHOGEN SYNONYM: Xanthomonas campestris pv. manihotis
SOURCE: A. Hayward
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 leaf spot (Bacterial necrosis)
HOST: Cassava
Cassava with yellowish leaves and water-soaked, angular spots. The disease is primarily on foliage, although the pathogen may invade stem buds and young branches.
Bacterial leaf spot (Bacterial necrosis) | Cassava
DISEASE: Bacterial leaf spot (Bacterial necrosis)
HOST: Cassava (Manihot esculenta)
PATHOGEN: Xanthomonas cassavae
PATHOGEN SYNONYM: Xanthomonas campestris pv. cassavae
SOURCE: APS
DISEASE: Bacterial leaf spot (Bacterial necrosis)
HOST: Cassava
Cassava with brownish lesions and blackish edges. Leaves turn yellow with multiple infection sites.
Bacterial leaf spot (Bacterial necrosis) | Cassava
DISEASE: Bacterial leaf spot (Bacterial necrosis)
HOST: Cassava (Manihot esculenta)
PATHOGEN: Xanthomonas cassavae
PATHOGEN SYNONYM: Xanthomonas campestris pv. cassavae
SOURCE: H. Maraite, A. Alvarez
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: 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