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 (Head rot)
HOST: Lettuce
Leaf with black, greasy spots that tend to be vein delimited. Lesions begin as small, angular, water-soaked lesions that coalesce, resulting in large necrotic areas.
Bacterial leaf spot (Head rot) | Lettuce
DISEASE: Bacterial leaf spot (Head rot)
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Xanthomonas axonopodis pv. vitians
PATHOGEN SYNONYM: Xanthomonas campestris pv. vitians
SOURCE: A. Alvarez
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
DISEASE: Corky root
HOST: Lettuce
Corky root causes a reduction in size of lettuce heads and root systems; susceptible cultivar (right) and resistant cultivar (left).
Corky root | Lettuce
DISEASE: Corky root
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Sphingomonas suberifaciens
PATHOGEN SYNONYM: Rhizomonas suberifaciens
SOURCE: E. J. Ryder