DISEASE: Aster yellows
HOST: Marigold
Infected plant (left) with yellowing and stunting.
Aster yellows | Marigold
DISEASE: Aster yellows
HOST: Marigold (Tagetes erecta)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: M. Shurtleff
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 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: Pseudomonas leaf spot
HOST: Marigold
Marigolds with yellow apical chlorosis attributed to toxin production by the pathogen.
Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin
DISEASE: Pseudomonas leaf spot
HOST: Marigold
Chlorotic leaves with total loss of chlorophyll. Disease is also known as toxic chlorosis.
Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin