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 leaf spot
HOST: Verbena
Leaf with purple-brown necrotic spots.
Bacterial leaf spot | Verbena
DISEASE: Bacterial leaf spot
HOST: Verbena (Verbena sp.)
PATHOGEN: Pseudomonas sp.
SOURCE: R. Raabe
DISEASE: Bacterial rot
HOST: Dracaena
Rot at base of leaves.
Bacterial rot | Dracaena
DISEASE: Bacterial rot
HOST: Dracaena (Dracaena deremensis)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: A. Alvarez
DISEASE: Bacterial rot
HOST: Dracaena
Systemic rot throughout central stems.
Bacterial rot | Dracaena
DISEASE: Bacterial rot
HOST: Dracaena (Dracaena deremensis)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: A. Chase
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