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: Bacterial wilt
HOST: Heliconia
Wilted and dying heliconia plant.

Bacterial wilt | Heliconia
DISEASE: Bacterial wilt
HOST: Heliconia (Heliconia sp.)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: I. Buddenhagen
DISEASE: Bacterial wilt
HOST: Heliconia
Heliconia spathes with wilt and leaf necrosis.

Bacterial wilt | Heliconia
DISEASE: Bacterial wilt
HOST: Heliconia (Heliconia sp.)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: I. Buddenhagen
DISEASE: Bacterial wilt
HOST: Heliconia
Heliconia stalk with discolored base.

Bacterial wilt | Heliconia
DISEASE: Bacterial wilt
HOST: Heliconia (Heliconia sp.)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: I. Buddenhagen
DISEASE: Bacterial wilt
HOST: Heliconia
Spathe of heliconia infected with bacterial wilt (right) compared with healthy spathe.

Bacterial wilt | Heliconia
DISEASE: Bacterial wilt
HOST: Heliconia (Heliconia sp.)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: I. Buddenhagen
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
DISEASE: Lethal yellowing
HOST: Palm
Palm with close-up of diseased yellow spear leaf.

Lethal yellowing | Palm
DISEASE: Lethal yellowing
HOST: Palm (Cocos nucifera)
PATHOGEN: 'Candidatus Phytoplasma palmae'
PATHOGEN SYNONYM: Phytoplasma Coconut lethal yellowing group
SOURCE: W. Sinclair
DISEASE: Lethal yellowing
HOST: Palm
Progression of lethal yellowing symptoms. Older fronds of coconut palm turn yellow, followed by yellowing of younger ones near center of crown.

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