DISEASE: Apple proliferation
HOST: Apple
Spring form of the adult black-veined psyllid, Cacopsylla melanoneura, a vector of apple proliferation. In winter, adults are more greenish in color.
Apple proliferation | Apple
DISEASE: Apple proliferation
HOST: Apple (Malus domestica)
PATHOGEN: 'Candidatus Phytoplasma mali'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: M. Wolf, W. Schweigkofler
DISEASE: Apple proliferation
HOST: Apple
Typical apple proliferation symptom of witches'-broom resulting from suppression of apical dominance and growth of dormant axillary buds. Branches are not usually bent down as shown here.
Apple proliferation | Apple
DISEASE: Apple proliferation
HOST: Apple (Malus domestica)
PATHOGEN: 'Candidatus Phytoplasma mali'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: M. Wolf, W. Schweigkofler
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: 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: Blister spot
HOST: Apple
Fruit with water-soaked spots.
Blister spot | Apple
DISEASE: Blister spot
HOST: Apple (Malus domestica)
PATHOGEN: Pseudomonas syringae pv. papulans
SOURCE: T. Burr
DISEASE: Blister spot
HOST: Apple
Water-soaked blister spots on leaves of blighted twig.
Blister spot | Apple
DISEASE: Blister spot
HOST: Apple (Malus domestica)
PATHOGEN: Pseudomonas syringae pv. papulans
SOURCE: T. Burr
DISEASE: Blossom blast
HOST: Apple
Many dead, shriveled flowers and young shoots. It differs from fire blight, with infections being relatively localized with the appearance of being "blasted".
Blossom blast | Apple
DISEASE: Blossom blast
HOST: Apple (Malus domestica)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: M. Schroth
DISEASE: Crown gall
HOST: Apple
Crown gall of apple.
Crown gall | Apple
DISEASE: Crown gall
HOST: Apple (Malus domestica)
PATHOGEN: Agrobacterium tumefaciens
PATHOGEN SYNONYM: Rhizobium sp.
SOURCE: H. Sawada, M. Goto