DISEASE: Aster yellows
HOST: Aster
Foliar symptoms of chlorosis, malformation of leaves, and phyllody.

Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. McCoy, M. Davis
DISEASE: Aster yellows
HOST: Aster
Flowers with phyllody (left and center). Healthy flower (right).

Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. McCoy, M. Davis
DISEASE: Aster yellows
HOST: Aster
Macrosteles sp., a leafhopper vector of aster yellows phytoplasma.

Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: J. Clark, A. Purcell, M. Davis
DISEASE: Bacterial blast and fruit spot
HOST: Avocado
White bacterial ooze on surface of fruit. Pseudomonas strains that cause canker likely differ from those that infect fruit and leaves.

Bacterial blast and fruit spot | Avocado
DISEASE: Bacterial blast and fruit spot
HOST: Avocado (Persea americana)
PATHOGEN: Pseudomonas syringae
SOURCE: L. Fucikovsky
DISEASE: Bacterial canker
HOST: Avocado
Cankers on trunk.

Bacterial canker | Avocado
DISEASE: Bacterial canker
HOST: Avocado (Persea americana)
PATHOGEN: Xanthomonas campestris
SOURCE: H. Ohr
DISEASE: Coffee leaf scorch
HOST: Coffee
Diseased twig with yellowish, stunted leaves (left). Healthy twig with normal-sized leaves (right).

Coffee leaf scorch | Coffee
DISEASE: Coffee leaf scorch
HOST: Coffee (Coffea arabica)
PATHOGEN: Xylella fastidiosa
SOURCE: S. Purcell
DISEASE: Halo blight
HOST: Coffee
Leaf with blackish lesions surrounded by yellow halos.

Halo blight | Coffee
DISEASE: Halo blight
HOST: Coffee (Coffea dewevrei)
PATHOGEN: Pseudomonas syringae pv. garcae
SOURCE: S. Mohan
DISEASE: Halo blight
HOST: Coffee
Young blighted coffee plant.

Halo blight | Coffee
DISEASE: Halo blight
HOST: Coffee (Coffea dewevrei)
PATHOGEN: Pseudomonas syringae pv. garcae
SOURCE: S. Mohan