DISEASE: Bacterial leaf scorch
HOST: Pecan
Pecan with necrotic scorched leaves with distinct dark lines between healthy and diseased tissues.

Bacterial leaf scorch | Pecan
DISEASE: Bacterial leaf scorch
HOST: Pecan (Carya illinoinensis)
PATHOGEN: Xylella fastidiosa
SOURCE: T. Brenneman
DISEASE: Bunch disease
HOST: Pecan
Pecan exhibiting bunch symptoms at ends of branches. This disease is thought to be caused by a phytoplasma similar to the walnut bunch pathogen in the X-disease group.

Bunch disease | Pecan
DISEASE: Bunch disease
HOST: Pecan (Carya illinoinensis)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: W. Sinclair
DISEASE: Bunch disease
HOST: Pecan
Severe case of bunch disease. Note bunches of foliage.

Bunch disease | Pecan
DISEASE: Bunch disease
HOST: Pecan (Carya illinoinensis)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: P. Bertrand
DISEASE: Pseudomonas leaf spot
HOST: Primrose
Leaf with brownish red spots and reddening of adjacent areas. Disease begins as small, water-soaked lesions that later coalesce into large necrotic spots.

Pseudomonas leaf spot | Primrose
DISEASE: Pseudomonas leaf spot
HOST: Primrose (Primula sp.)
PATHOGEN: Pseudomonas syringae pv. primulae
SOURCE: APS
DISEASE: Witches'-broom
HOST: Pecan
Diseased pecan with short branches on trunk with witches'-broom appearance.

Witches'-broom | Pecan
DISEASE: Witches'-broom
HOST: Pecan (Carya illinoinensis)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: P. Bertrand
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