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: Bacterial leaf spot
HOST: Croton
Tan, irregular-sized lesions on lower leaf surfaces.

Bacterial leaf spot | Croton
DISEASE: Bacterial leaf spot
HOST: Croton (Codiaeum variegatum var. pictum)
PATHOGEN: Xanthomonas axonopodis pv. poinsettiicola
PATHOGEN SYNONYM: Xanthomonas campestris pv. poinsettiicola
SOURCE: J. Yuen
DISEASE: Bacterial leaf spot
HOST: Croton
Leaves with dry, irregularly shaped, brown necrotic areas.

Bacterial leaf spot | Croton
DISEASE: Bacterial leaf spot
HOST: Croton (Codiaeum variegatum)
PATHOGEN: Xanthomonas codiaei
SOURCE: A. Chase
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: Citrus greening (Huanglongbing)
HOST: Citrus (Mandarin orange)
The bacterium invades the tree slowly, leading to yellowing of the entire canopy. Pale yellow, blotchy mottled leaves are reduced in size.

Citrus greening (Huanglongbing) | Citrus (Mandarin orange)
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (Mandarin orange) (Citrus reticulata)
PATHOGEN: 'Candidatus Liberibacter asiaticus'
PATHOGEN SYNONYM: Candidatus Liberobacter asiaticus
SOURCE: S. M. Garnsey