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 leaf spot
HOST: Cowpea
Leaf spots vary in size from small to large and some fall out in time, leaving a shot-hole appearance.

Bacterial leaf spot | Cowpea
DISEASE: Bacterial leaf spot
HOST: Cowpea (Vigna unguiculata)
PATHOGEN: Xanthomonas axonopodis pv. vignicola
PATHOGEN SYNONYM: Xanthomonas campestris pv. vignicola
SOURCE: R. Gitaitis
DISEASE: Bacterial leaf spot
HOST: Cowpea
Leaves with large, light brown necrotic areas.

Bacterial leaf spot | Cowpea
DISEASE: Bacterial leaf spot
HOST: Cowpea (Vigna unguiculata)
PATHOGEN: Xanthomonas axonopodis pv. vignicola
PATHOGEN SYNONYM: Xanthomonas campestris pv. vignicola
SOURCE: R. Gitaitis
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
DISEASE: Lethal yellowing
HOST: Palm
Coconut palm with yellowing and desiccation of leaves, late stage of disease.

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