DISEASE: Aster yellows
HOST: Squash
Diagnostic characteristics for the disease are yellowing of young leaves, proliferation of secondary shoots, and rigid erect habit. Leaves are misshapen and smaller than normal and have stiff, thick laminae.

Aster yellows | Squash
DISEASE: Aster yellows
HOST: Squash (Cucurbita sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Miller
DISEASE: Bacterial heart rot
HOST: Palm
Palm with advanced stage of heart rot. Symptoms of mature palms include rapid browning and desiccation of foliage, rot of roots and buds, and aborted fruits.

Bacterial heart rot | Palm
DISEASE: Bacterial heart rot
HOST: Palm (Cocos nucifera)
PATHOGEN: Phytomonas sp.
SOURCE: R. McCoy, M. Davis
DISEASE: Bunch disease
HOST: Walnut
Twisted shoot with yellow leaves, a symptom of bunch disease.

Bunch disease | Walnut
DISEASE: Bunch disease
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: E. Braun
DISEASE: Deep bark canker
HOST: Walnut
Reddish brown exudate flowing from longitudinal cracks in the trunk. Cankers are deep extending into wood.

Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: B. Teviotdale
DISEASE: Deep bark canker
HOST: Walnut
Reddish brown exudate flowing from cracks in trunk, a result of systemic invasion by the bacterium.

Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: B. Teviotdale
DISEASE: Deep bark canker
HOST: Walnut
Removal of bark revealed pitted vascular tissues.

Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: N. Schaad
DISEASE: Deep bark canker
HOST: Walnut
Dead limbs are characteristic of advanced stage of disease.

Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: N. Schaad
DISEASE: Lethal yellowing
HOST: Palm
Palm with dark necrotic inflorescence.

Lethal yellowing | Palm
DISEASE: Lethal yellowing
HOST: Palm (Cocos nucifera)
PATHOGEN: 'Candidatus Phytoplasma palmae'
PATHOGEN SYNONYM: Phytoplasma Coconut lethal yellowing group
SOURCE: N. A. Harrison