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: Larkspur
Infected leaflets with many purplish spots with necrotic centers.
Bacterial leaf spot | Larkspur
DISEASE: Bacterial leaf spot
HOST: Larkspur (Delphinium sp.)
PATHOGEN: Pseudomonas syringae pv. delphinii
SOURCE: R. Raabe
DISEASE: Black chaff (Bacterial leaf streak)
HOST: Wheatgrass
Lesions on leaves first appear as water-soaked, translucent, long, narrow streaks. They later turn brown and necrotic and often coalesce into blighted areas.
Black chaff (Bacterial leaf streak) | Wheatgrass
DISEASE: Black chaff (Bacterial leaf streak)
HOST: Wheatgrass (Elytrigia intermedia)
PATHOGEN: Xanthomonas translucens pv. cerealis
SOURCE: S. Mohan
DISEASE: Black chaff (Bacterial leaf streak)
HOST: Wheatgrass
Close-up of leaf with brown necrotic streaks.
Black chaff (Bacterial leaf streak) | Wheatgrass
DISEASE: Black chaff (Bacterial leaf streak)
HOST: Wheatgrass (Elytrigia intermedia)
PATHOGEN: Xanthomonas translucens pv. cerealis
SOURCE: S. Mohan
DISEASE: Larkspur virescence
HOST: Larkspur
Two diseased plants with stunted and small leaves, lack of flower coloration, and bunched flower buds. Healthy plant (left).
Larkspur virescence | Larkspur
DISEASE: Larkspur virescence
HOST: Larkspur (Delphinium sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Raabe
DISEASE: Lethal decline
HOST: Palm
Date palm exhibiting symptoms of lethal decline.
Lethal decline | Palm
DISEASE: Lethal decline
HOST: Palm (Phoenix dactylifera)
PATHOGEN: 'Candidatus Phytoplasma palmae'
PATHOGEN SYNONYM: Phytoplasma Coconut lethal yellowing group
SOURCE: W. Sinclair
DISEASE: Lethal decline
HOST: Palm
Date palm with late stage of lethal decline.
Lethal decline | Palm
DISEASE: Lethal decline
HOST: Palm (Phoenix dactylifera)
PATHOGEN: 'Candidatus Phytoplasma palmae'
PATHOGEN SYNONYM: Phytoplasma Coconut lethal yellowing group
SOURCE: W. Sinclair
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