DISEASE: Aster yellows
HOST: Potato
Chlorotic and stunted foliage with necrotic leaf margins. Other symptoms may be phyllody, virescence, purple or yellow pigmentation, and rolling of leaflets.
Aster yellows | Potato
DISEASE: Aster yellows
HOST: Potato (Solanum tuberosum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson
DISEASE: Aster yellows
HOST: Potato
Stunted, chlorotic plants (left) with stiff, rolled leaves.
Aster yellows | Potato
DISEASE: Aster yellows
HOST: Potato (Solanum tuberosum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson
DISEASE: Aster yellows
HOST: Potato
Diseased plant with malformed tubers.
Aster yellows | Potato
DISEASE: Aster yellows
HOST: Potato (Solanum tuberosum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson
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: Cabbage
Cabbage leaves with irregular, brownish lesions. The bacterium does not invade vascular tissues.
Bacterial leaf spot | Cabbage
DISEASE: Bacterial leaf spot
HOST: Cabbage (Brassica oleracea var. capitata)
PATHOGEN: Xanthomonas campestris pv. armoraciae
SOURCE: R. Gitaitis
DISEASE: Bacterial leaf spot
HOST: Cabbage
Water-soaked lesions on underside of leaf (left), and water-soaked, large necrotic lesions on upper side (right).
Bacterial leaf spot | Cabbage
DISEASE: Bacterial leaf spot
HOST: Cabbage (Brassica oleracea var. capitata)
PATHOGEN: Xanthomonas campestris pv. armoraciae
SOURCE: R. Campbell
DISEASE: Bacterial leaf spot
HOST: Cabbage
Leaf with various stages of lesion development, including water-soaked lesions.
Bacterial leaf spot | Cabbage
DISEASE: Bacterial leaf spot
HOST: Cabbage (Brassica oleracea var. capitata)
PATHOGEN: Xanthomonas campestris pv. armoraciae
SOURCE: R. Campbell
DISEASE: Bacterial leaf spot
HOST: Cabbage
Cabbage leaves with many irregular, dark, water-soaked lesions.
Bacterial leaf spot | Cabbage
DISEASE: Bacterial leaf spot
HOST: Cabbage (Brassica oleracea var. capitata)
PATHOGEN: Xanthomonas campestris pv. armoraciae
SOURCE: R. Gitaitis
DISEASE: Bacterial leaf spot
HOST: Cabbage
Necrotic, light tan leaf spots, a late stage in disease development.
Bacterial leaf spot | Cabbage
DISEASE: Bacterial leaf spot
HOST: Cabbage (Brassica pekinensis)
PATHOGEN: Xanthomonas campestris pv. armoraciae
SOURCE: R. Campbell