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 canker (Leaf and fruit spot)
HOST: Kiwi
Diseased blossoms, a stage of bacterial canker.
Bacterial canker (Leaf and fruit spot) | Kiwi
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi (Actinidia chinensis)
PATHOGEN: Pseudomonas syringae pv. actinidiae
SOURCE: J. Young
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi
Leaf spot stage of the disease with small, brown lesions with yellow halos.
Bacterial canker (Leaf and fruit spot) | Kiwi
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi (Actinidia chinensis)
PATHOGEN: Pseudomonas syringae pv. actinidiae
SOURCE: M. Goto
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi
Leaf spots on young leaves. Note dark brown to black lesions on lower surface (left) and similar lesions on upper surface but with yellow halos (right).
Bacterial canker (Leaf and fruit spot) | Kiwi
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi (Actinidia chinensis)
PATHOGEN: Pseudomonas syringae pv. actinidiae
SOURCE: J. Young
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi
Rusty-colored exudate oozing from cankers on infected trunk.
Bacterial canker (Leaf and fruit spot) | Kiwi
DISEASE: Bacterial canker (Leaf and fruit spot)
HOST: Kiwi (Actinidia chinensis)
PATHOGEN: Pseudomonas syringae pv. actinidiae
SOURCE: M. Goto
DISEASE: Bacterial leaf spot
HOST: Nephthytis
Leaf with concentric rings of dark tissues. There has been confusion of the causal agent with Dickeya sp., which also causes mushy leaf spots.
Bacterial leaf spot | Nephthytis
DISEASE: Bacterial leaf spot
HOST: Nephthytis (Syngonium podophyllum)
PATHOGEN: Pectobacterium carotovorum
PATHOGEN SYNONYM: Erwinia carotovora subsp. carotovora
SOURCE: A. Chase
DISEASE: Bacterial leaf spot
HOST: Nephthytis
Water-soaked tissues and large, dark brown necrotic areas at leaf margins. Healthy (center leaf).
Bacterial leaf spot | Nephthytis
DISEASE: Bacterial leaf spot
HOST: Nephthytis (Syngonium podophyllum)
PATHOGEN: Pseudomonas cichorii
SOURCE: S. Thomson
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: Kiwi
Crown gall of kiwi.
Crown gall | Kiwi
DISEASE: Crown gall
HOST: Kiwi (Actinidia chinensis)
PATHOGEN: Agrobacterium tumefaciens
PATHOGEN SYNONYM: Rhizobium sp.
SOURCE: H. Sawada, M. Goto