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: Blister spot
HOST: Apple
Late stage of blister spot. The purplish black lesions are associated with lenticels and stomata.
Blister spot | Apple
DISEASE: Blister spot
HOST: Apple (Malus domestica 'Crispin')
PATHOGEN: Pseudomonas syringae pv. papulans
SOURCE: T. Burr
DISEASE: Crown gall
HOST: Grape
Gall on base of 'Zinfandel' grape in California, where aerial galls are less common because of dry, hot weather.
Crown gall | Grape
DISEASE: Crown gall
HOST: Grape (Vitis vinifera 'Zinfandel')
PATHOGEN: Agrobacterium vitis
PATHOGEN SYNONYM: Rhizobium vitus
SOURCE: M. Schroth