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 blast and fruit spot
HOST: Avocado
White bacterial ooze on surface of fruit. Pseudomonas strains that cause canker likely differ from those that infect fruit and leaves.
Bacterial blast and fruit spot | Avocado
DISEASE: Bacterial blast and fruit spot
HOST: Avocado (Persea americana)
PATHOGEN: Pseudomonas syringae
SOURCE: L. Fucikovsky
DISEASE: Bacterial canker
HOST: Avocado
Cankers on trunk.
Bacterial canker | Avocado
DISEASE: Bacterial canker
HOST: Avocado (Persea americana)
PATHOGEN: Xanthomonas campestris
SOURCE: H. Ohr
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: Oleander knot
HOST: Oleander
Oleander with small knots/galls on leaf and stems.
Oleander knot | Oleander
DISEASE: Oleander knot
HOST: Oleander (Nerium oleander)
PATHOGEN: Pseudomonas savastanoi pv. nerii
SOURCE: W. Sinclair
DISEASE: Oleander knot
HOST: Oleander
Young stem with knots/galls.
Oleander knot | Oleander
DISEASE: Oleander knot
HOST: Oleander (Nerium oleander)
PATHOGEN: Pseudomonas savastanoi pv. nerii
SOURCE: R. Raabe
DISEASE: Oleander knot
HOST: Oleander
Leaf with early stage of knot/gall formation.
Oleander knot | Oleander
DISEASE: Oleander knot
HOST: Oleander (Nerium oleander)
PATHOGEN: Pseudomonas savastanoi pv. nerii
SOURCE: R. Raabe
DISEASE: Oleander knot
HOST: Oleander
Infected flowers with small knots/galls and necroses.
Oleander knot | Oleander
DISEASE: Oleander knot
HOST: Oleander (Nerium oleander)
PATHOGEN: Pseudomonas savastanoi pv. nerii
SOURCE: W. Sinclair
DISEASE: Oleander leaf scorch
HOST: Oleander
Diseased plant with scalloped, yellowish leaves. This usually is followed by dieback of twigs and branches. Plants often die 2 years after infection.
Oleander leaf scorch | Oleander
DISEASE: Oleander leaf scorch
HOST: Oleander (Nerium oleander)
PATHOGEN: Xylella fastidiosa
SOURCE: S. Purcell