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 stem rot
HOST: Dieffenbachia
Dieffenbachia with rot and decay of stem and leaf tissues.
Bacterial stem rot | Dieffenbachia
DISEASE: Bacterial stem rot
HOST: Dieffenbachia (Dieffenbachia seguine)
PATHOGEN: Dickeya dieffenbachiae
PATHOGEN SYNONYM: Erwinia chrysanthemi pv. dieffenbachiae
SOURCE: A. Alvarez
DISEASE: Bacterial stem rot
HOST: Dieffenbachia
Dieffenbachia with wilted and rotted leaves.
Bacterial stem rot | Dieffenbachia
DISEASE: Bacterial stem rot
HOST: Dieffenbachia (Dieffenbachia seguine)
PATHOGEN: Dickeya dieffenbachiae
PATHOGEN SYNONYM: Erwinia chrysanthemi pv. dieffenbachiae
SOURCE: R. Raabe
DISEASE: Bacterial stem rot
HOST: Dieffenbachia
Cross section of stem exposing rotted tissues.
Bacterial stem rot | Dieffenbachia
DISEASE: Bacterial stem rot
HOST: Dieffenbachia (Dieffenbachia seguine)
PATHOGEN: Dickeya dieffenbachiae
PATHOGEN SYNONYM: Erwinia chrysanthemi pv. dieffenbachiae
SOURCE: R. Raabe
DISEASE: Bacterial stem rot
HOST: Dieffenbachia
Leaf with rot and wilt.
Bacterial stem rot | Dieffenbachia
DISEASE: Bacterial stem rot
HOST: Dieffenbachia (Dieffenbachia seguine)
PATHOGEN: Dickeya dieffenbachiae
PATHOGEN SYNONYM: Erwinia chrysanthemi pv. dieffenbachiae
SOURCE: R. Raabe
DISEASE: Elm yellows
HOST: Elm
Symptoms of elm yellows occasionally appear on one branch before others, but more often they involve the entire crown.
Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus americana)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair
DISEASE: Elm yellows
HOST: Elm
Diseased twig (right) with epinasty, chlorosis, and yellowing of leaves. Sometimes both yellow and green leaves occur on same branch. Healthy branch (left).
Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus americana)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair
DISEASE: Elm yellows
HOST: Elm
Branches with butterscotch discoloration (center) and necrotic flecks in phloem and vascular cambium (right). Healthy branch (left). Sudden wilt and browning is common with small trees.
Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus americana)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair
DISEASE: Elm yellows
HOST: Elm
Elm yellows is characterized by witches'-brooms and stunting. Some cultivars have both yellow and reddish foliar discoloration.
Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus parvifolia)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair