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 leaf spot
HOST: Cherry laurel
Leaves with typical necrotic spots.

Bacterial leaf spot | Cherry laurel
DISEASE: Bacterial leaf spot
HOST: Cherry laurel (Prunus laurocerasus)
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: A. Hagen, W. Sinclair
DISEASE: Bacterial leaf spot
HOST: Magnolia
Leaf with black, angular spots.

Bacterial leaf spot | Magnolia
DISEASE: Bacterial leaf spot
HOST: Magnolia (Magnolia soulangiana)
PATHOGEN: Pseudomonas cichorii
SOURCE: R. Raabe
DISEASE: Bacterial leaf spot
HOST: Magnolia
Leaf with large, dark brown to black necrotic areas.

Bacterial leaf spot | Magnolia
DISEASE: Bacterial leaf spot
HOST: Magnolia (Magnolia grandiflora)
PATHOGEN: Pseudomonas cichorii
SOURCE: J. Mullen
DISEASE: Bacterial wilt
HOST: Squash
Field with severe symptoms of wilt. Foliage often is chlorotic and leaf margins may be chlorotic and necrotic before plant death. Bacterial ooze may be seen streaming from the xylem when infected stems are cut.

Bacterial wilt | Squash
DISEASE: Bacterial wilt
HOST: Squash (Cucurbita maxima)
PATHOGEN: Erwinia tracheiphila
SOURCE: B. Jacobsen, M. Shurtleff