DISEASE: Bacterial leaf spot
HOST: Larkspur
Infected leaflets with many purplish spots with necrotic centers.
Bacterial leaf spot | Larkspur
DISEASE: Bacterial leaf spot
HOST: Larkspur (Delphinium sp.)
PATHOGEN: Pseudomonas syringae pv. delphinii
SOURCE: R. Raabe
DISEASE: Dogwood stunt
HOST: Dogwood
Diseased plant with small leaves (left).
Dogwood stunt | Dogwood
DISEASE: Dogwood stunt
HOST: Dogwood (Cornus sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: W. Sinclair
DISEASE: Drippy nut disease
HOST: Oak
Ooze from young twig inoculated with Brenneria quercina.
Drippy nut disease | Oak
DISEASE: Drippy nut disease
HOST: Oak (Quercus agrifolia)
PATHOGEN: Brenneria quercina
PATHOGEN SYNONYM: Erwinia quercina
SOURCE: M. Schroth
DISEASE: Drippy nut disease
HOST: Oak
Ooze from infected acorn. Copious ooze drips from infected acorns, leaving sticky spots on objects under tree canopy. Infections are associated with insect oviposit wounds.
Drippy nut disease | Oak
DISEASE: Drippy nut disease
HOST: Oak (Quercus agrifolia)
PATHOGEN: Brenneria quercina
PATHOGEN SYNONYM: Erwinia quercina
SOURCE: M. Schroth
DISEASE: Larkspur virescence
HOST: Larkspur
Two diseased plants with stunted and small leaves, lack of flower coloration, and bunched flower buds. Healthy plant (left).
Larkspur virescence | Larkspur
DISEASE: Larkspur virescence
HOST: Larkspur (Delphinium sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Raabe
DISEASE: Witches'-broom
HOST: Dogwood
Witches'-broom of eastern dogwood.
Witches'-broom | Dogwood
DISEASE: Witches'-broom
HOST: Dogwood (Cornus sp.)
PATHOGEN: 'Candidatus Phytoplasma' sp.
PATHOGEN SYNONYM: Phytoplasma (undefined)
SOURCE: W. Sinclair