DISEASE: Apple proliferation
HOST: Apple
Enlarged stipules on leaf. Witches'-brooms, rosettes, and enlarged stipules are the most reliable symptoms for identification.
Apple proliferation | Apple
DISEASE: Apple proliferation
HOST: Apple (Malus domestica 'Granny Smith')
PATHOGEN: 'Candidatus Phytoplasma mali'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: M. Wolf, W. Schweigkofler
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: Bacterial blight
HOST: Tulip
The disease causes white veins of leaves, yellow vascular bundles, and yellow bacterial slime on bulbs.
Bacterial blight | Tulip
DISEASE: Bacterial blight
HOST: Tulip (Tulipa sp. 'Paul Richter')
PATHOGEN: Curtobacterium flaccumfaciens pv. oortii
PATHOGEN SYNONYM: Corynebacterium flaccumfaciens subsp. oortii
SOURCE: M. Geesteranus, J. van der Wolf
DISEASE: Bacterial blight
HOST: Tulip
Stunted plants with wrinkled leaves.
Bacterial blight | Tulip
DISEASE: Bacterial blight
HOST: Tulip (Tulipa sp. 'Paul Richter')
PATHOGEN: Curtobacterium flaccumfaciens pv. oortii
PATHOGEN SYNONYM: Corynebacterium flaccumfaciens subsp. oortii
SOURCE: M. Geesteranus, J. van der Wolf
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