DISEASE: Bacterial blast
HOST: Pear
The bacterium infects all flower parts and may spread and kill the entire spur.

Bacterial blast | Pear
DISEASE: Bacterial blast
HOST: Pear (Pyrus communis)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: W. Sinclair
DISEASE: Bacterial dieback of nectarine
HOST: Nectarine
Fruit lesions is another symptom of this disease.

Bacterial dieback of nectarine | Nectarine
DISEASE: Bacterial dieback of nectarine
HOST: Nectarine (Prunus persica var. nucipersica 'Redgold')
PATHOGEN: Pseudomonas syringae pv. persicae
SOURCE: J. Young
DISEASE: Bacterial spot
HOST: Nectarine
Nectarine with necrotic spots on leaves and dark necrotic spots on fruit.

Bacterial spot | Nectarine
DISEASE: Bacterial spot
HOST: Nectarine (Prunus persica var. nucipersica 'Redgold')
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: J. Young
DISEASE: Crown gall
HOST: Pear
Crown gall of pear rootstock.

Crown gall | Pear
DISEASE: Crown gall
HOST: Pear (Pyrus communis)
PATHOGEN: Agrobacterium tumefaciens
PATHOGEN SYNONYM: Rhizobium sp.
SOURCE: H. Sawada, M. Goto
DISEASE: Fire blight
HOST: Pear
Blighted shoot and blossoms.

Fire blight | Pear
DISEASE: Fire blight
HOST: Pear (Pyrus communis)
PATHOGEN: Erwinia amylovora
SOURCE: M. Schroth
DISEASE: Fire blight
HOST: Pear
Typical appearance of advanced stage of disease after the bacterium invades from shoot tips/flowers downward.

Fire blight | Pear
DISEASE: Fire blight
HOST: Pear (Pyrus communis)
PATHOGEN: Erwinia amylovora
SOURCE: M. Schroth
DISEASE: Fire blight
HOST: Pear
The disease causes lack of leaf detachment on infected branches, commonly seen during California winters.

Fire blight | Pear
DISEASE: Fire blight
HOST: Pear (Pyrus communis)
PATHOGEN: Erwinia amylovora
SOURCE: M. Schroth
DISEASE: Fire blight
HOST: Pear
Diseased fruit.

Fire blight | Pear
DISEASE: Fire blight
HOST: Pear (Pyrus communis)
PATHOGEN: Erwinia amylovora
SOURCE: M. Schroth