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: 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: Ginger
Blackening of pith and cortex of rhizome.
Bacterial wilt | Ginger
DISEASE: Bacterial wilt
HOST: Ginger (Zingiber officinale)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: A. Alvarez
DISEASE: Bacterial wilt
HOST: Ginger
Field of wilted ginger plants.
Bacterial wilt | Ginger
DISEASE: Bacterial wilt
HOST: Ginger (Zingiber officinale)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: A. Hayward
DISEASE: Bacterial wilt
HOST: Ginger
Ginger plants with yellowing, marginal necrosis, and downward curling of infected leaves, in contrast to darker, fully expanded healthy leaves.
Bacterial wilt | Ginger
DISEASE: Bacterial wilt
HOST: Ginger (Zingiber officinale)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: M. Paret, N. Joy
DISEASE: Bacterial wilt
HOST: Ginger
Cupping and leaf necrosis precedes wilt and death of plants.
Bacterial wilt | Ginger
DISEASE: Bacterial wilt
HOST: Ginger (Zingiber officinale)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: M. Paret, N. Joy
DISEASE: Bacterial wilt
HOST: Ginger
Typical symptoms of bacterial wilt in ginger plantations, Kerala, India.
Bacterial wilt | Ginger
DISEASE: Bacterial wilt
HOST: Ginger (Zingiber officinale)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: M. Paret, N. Joy
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