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 dieback of peach
HOST: Peach
Dark cankers on last year's twig. This leads to blighting of buds the following year.
Bacterial dieback of peach | Peach
DISEASE: Bacterial dieback of peach
HOST: Peach (Prunus persica)
PATHOGEN: Pseudomonas syringae pv. persicae
SOURCE: J. Young
DISEASE: Bacterial spot
HOST: Peach
Pitted fruit caused by late season infection.
Bacterial spot | Peach
DISEASE: Bacterial spot
HOST: Peach (Prunus persica)
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: E. Zehr
DISEASE: Bacterial spot
HOST: Peach
Fruit infected late in the season.
Bacterial spot | Peach
DISEASE: Bacterial spot
HOST: Peach (Prunus persica)
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: T. Burr
DISEASE: Bacterial spot
HOST: Peach
Reddish lesions on young twig (left). Dead buds are visible (right), the result of previous year's infection of twig.
Bacterial spot | Peach
DISEASE: Bacterial spot
HOST: Peach (Prunus persica)
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: D. Ritchie
DISEASE: Bacterial spot
HOST: Peach
Leaves with water-soaked and necrotic spots.
Bacterial spot | Peach
DISEASE: Bacterial spot
HOST: Peach (Prunus persica)
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: D. Ritchie
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