DISEASE: Aster yellows
HOST: Chrysanthemum
Stunted diseased plant with small distorted flowers.
Aster yellows | Chrysanthemum
DISEASE: Aster yellows
HOST: Chrysanthemum (Chrysanthemum morifolium)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: B. Raju, M. Davis
DISEASE: Bacterial blight
HOST: Hazelnut
Diseased young tree with discoloration of the cambium. Dieback of young twigs and branches is characteristic. Other typical symptoms are bud and twig necrosis and small, angular or round, water-soaked leaf spots.
Bacterial blight | Hazelnut
DISEASE: Bacterial blight
HOST: Hazelnut (Corylus americana)
PATHOGEN: Xanthomonas arboricola pv. corylina
SOURCE: J. Pscheidt
DISEASE: Bacterial canker
HOST: Hazelnut
Primary symptoms are failure of buds to break and withering and death of new foliage in spring. Dead leaves remain attached to limbs after normal leaf fall.
Bacterial canker | Hazelnut
DISEASE: Bacterial canker
HOST: Hazelnut (Corylus americana)
PATHOGEN: Pseudomonas syringae pv. avellanae
PATHOGEN SYNONYM: Pseudomonas avellanae
SOURCE: P. Psalidas
DISEASE: Bacterial fasciation (Leafy gall)
HOST: Chrysanthemum
Fasciation of chrysanthemum.
Bacterial fasciation (Leafy gall) | Chrysanthemum
DISEASE: Bacterial fasciation (Leafy gall)
HOST: Chrysanthemum (Chrysanthemum morifolium)
PATHOGEN: Rhodococcus fascians
SOURCE: M. Schroth
DISEASE: Bacterial wilt and blight
HOST: Chrysanthemum
Plants with characteristic symptoms of wilt.
Bacterial wilt and blight | Chrysanthemum
DISEASE: Bacterial wilt and blight
HOST: Chrysanthemum (Chrysanthemum morifolium)
PATHOGEN: Dickeya sp.
PATHOGEN SYNONYM: Erwinia chrysanthemi
SOURCE: A. Alvarez
DISEASE: Crown gall
HOST: Chrysanthemum
Galls on chrysanthemum stem.
Crown gall | Chrysanthemum
DISEASE: Crown gall
HOST: Chrysanthemum (Chrysanthemum morifolium)
PATHOGEN: Agrobacterium tumefaciens
PATHOGEN SYNONYM: Rhizobium sp.
SOURCE: K. Ohta, M. Goto
DISEASE: Greening disease
HOST: Periwinkle
Healthy flower and infected flower.
Greening disease | Periwinkle
DISEASE: Greening disease
HOST: Periwinkle (Vinca sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: D. Teakle
DISEASE: Periwinkle wilt
HOST: Periwinkle
Infected plants with stunting and sparse foliage (center and right).
Periwinkle wilt | Periwinkle
DISEASE: Periwinkle wilt
HOST: Periwinkle (Vinca sp.)
PATHOGEN: Xylella fastidiosa
SOURCE: R. McCoy, M. Davis
DISEASE: Periwinkle wilt
HOST: Periwinkle
Draeculacephala minerva, leafhopper vector of Xylella fastidiosa on plants such as periwinkle and watercress.
Periwinkle wilt | Periwinkle
DISEASE: Periwinkle wilt
HOST: Periwinkle (Vinca sp.)
PATHOGEN: Xylella fastidiosa
SOURCE: J. Clark, A. Purcell, M. Davis