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 blight (Leaf spot)
HOST: Clover
Diseased leaf with elongated, reddish brown lesions, especially numerous on the margins.

Bacterial blight (Leaf spot) | Clover
DISEASE: Bacterial blight (Leaf spot)
HOST: Clover (Trifolium alexandrinum)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: M. Shurtleff
DISEASE: Bacterial leaf spot
HOST: Hydrangea (Oak-leaf)
Leaf with individual brown necrotic lesions and coalesced lesions that formed large necrotic areas. The disease is caused by an unclassified xanthomonad.

Bacterial leaf spot | Hydrangea (Oak-leaf)
DISEASE: Bacterial leaf spot
HOST: Hydrangea (Oak-leaf) (Hydrangea quercifolia)
PATHOGEN: Xanthomonas campestris
SOURCE: W. Uddin, W. Sinclair