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: 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: Pear decline
HOST: Pear
'Bartlett' pears were grafted onto tolerant rootstock. All trees are infected. Note yellowish, diseased branches.
Pear decline | Pear
DISEASE: Pear decline
HOST: Pear (Pyrus communis 'Bartlett')
PATHOGEN: 'Candidatus Phytoplasma pyri'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: C. Smart
DISEASE: X-disease (Western X) or buckskin
HOST: Cherry
X-disease causes undersized, yellowish fruit. Diseased branches turn rusty red near end of season. Some defoliation occurs on diseased branches.
X-disease (Western X) or buckskin | Cherry
DISEASE: X-disease (Western X) or buckskin
HOST: Cherry (Prunus cerasus)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: A. Jones