DISEASE: Aster yellows
HOST: Watercress
Diseased watercress (left) and healthy plant (right).

Aster yellows | Watercress
DISEASE: Aster yellows
HOST: Watercress (Nasturtium officinale)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: W. Borth
DISEASE: Aster yellows
HOST: Wheat
Healthy head (left) and diseased head (right). Diseased seedlings may die within 2 to 3 weeks. Infected heads of surviving plants are small and sterile, with distorted awns.

Aster yellows | Wheat
DISEASE: Aster yellows
HOST: Wheat (Triticum aestivum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: L. N. Chiykowski
DISEASE: Aster yellows
HOST: Zinnia
Yellowing and shoot proliferation of foliage.

Aster yellows | Zinnia
DISEASE: Aster yellows
HOST: Zinnia (Zinnia violacea)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: J. Forsberg, M. Shurtleff
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (sp. unknown)
Citrus psyllid (Diaphorina citri), a vector of 'Candidatus Liberibacter asiaticus', the cause of citrus greening, feeding on green twig.

Citrus greening (Huanglongbing) | Citrus (sp. unknown)
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (sp. unknown) (Citrus sp.)
PATHOGEN: 'Candidatus Liberibacter asiaticus'
PATHOGEN SYNONYM: Candidatus Liberobacter asiaticus
SOURCE: C. Jacobson
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (sp. unknown)
Citrus psyllid (Diaphorina citri), a vector of 'Candidatus Liberibacter asiaticus', the cause of citrus greening.

Citrus greening (Huanglongbing) | Citrus (sp. unknown)
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (sp. unknown) (Citrus sp.)
PATHOGEN: 'Candidatus Liberibacter asiaticus'
PATHOGEN SYNONYM: Candidatus Liberobacter asiaticus
SOURCE: C. Jacobson
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (sp. unknown)
Citrus psyllid (Diaphorina citri), a vector of 'Candidatus Liberibacter asiaticus', the cause of citrus greening.

Citrus greening (Huanglongbing) | Citrus (sp. unknown)
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (sp. unknown) (Citrus sp.)
PATHOGEN: 'Candidatus Liberibacter asiaticus'
PATHOGEN SYNONYM: Candidatus Liberobacter asiaticus
SOURCE: C. Hirayama
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (Orange)
Mature infected fruit may be misshapen and vary in degree of greening.

Citrus greening (Huanglongbing) | Citrus (Orange)
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (Orange) (Citrus sinensis)
PATHOGEN: 'Candidatus Liberibacter asiaticus'
PATHOGEN SYNONYM: Candidatus Liberobacter asiaticus
SOURCE: R. McCoy, M. Davis
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (Orange)
Leaves with yellowish mottle resembling nutrient deficiency.

Citrus greening (Huanglongbing) | Citrus (Orange)
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (Orange) (Citrus sinensis)
PATHOGEN: 'Candidatus Liberibacter asiaticus'
PATHOGEN SYNONYM: Candidatus Liberobacter asiaticus
SOURCE: D. Gabriel
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (Orange)
Mature, misshapen diseased fruit. Healthy fruit (lower left).

Citrus greening (Huanglongbing) | Citrus (Orange)
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (Orange) (Citrus sinensis)
PATHOGEN: 'Candidatus Liberibacter asiaticus'
PATHOGEN SYNONYM: Candidatus Liberobacter asiaticus
SOURCE: P. Broadbent