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 stem and root rot
HOST: Sweet potato
Collapse of stems and roots caused by systemic activity of the pathogen.
Bacterial stem and root rot | Sweet potato
DISEASE: Bacterial stem and root rot
HOST: Sweet potato (Ipomoea batatas)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: N. Schaad
DISEASE: Bacterial stem and root rot
HOST: Sweet potato
Rot and collapse of stem, petioles, and leaves caused by systemic infection.
Bacterial stem and root rot | Sweet potato
DISEASE: Bacterial stem and root rot
HOST: Sweet potato (Ipomoea batatas)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: N. Schaad
DISEASE: Bacterial stem and root rot
HOST: Sweet potato
Rot and internal discoloration of tuber.
Bacterial stem and root rot | Sweet potato
DISEASE: Bacterial stem and root rot
HOST: Sweet potato (Ipomoea batatas)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: C. Clark
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