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
DISEASE: Bacterial leaf spot
HOST: Turnip
Leaf with many tan, dry-appearing, angular spots.

Bacterial leaf spot | Turnip
DISEASE: Bacterial leaf spot
HOST: Turnip (Brassica rapa)
PATHOGEN: Xanthomonas campestris pv. armoraciae
SOURCE: R. Campbell
DISEASE: European stone fruit yellows
HOST: Almond
The disease causes yellowing and rolling of leaves (right). Leaves become thick and rough in texture. Healthy leaves (left).

European stone fruit yellows | Almond
DISEASE: European stone fruit yellows
HOST: Almond (Prunus dulcis)
PATHOGEN: 'Candidatus Phytoplasma prunorum'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: E. Seemueller
DISEASE: Xanthomonas leaf blight
HOST: Onion
This was the first photo of onion leaf blight, which was considered a controversial finding for 10 years until an outbreak occurred in the West Indies.

Xanthomonas leaf blight | Onion
DISEASE: Xanthomonas leaf blight
HOST: Onion (Allium cepa)
PATHOGEN: Xanthomonas axonopodis pv. allii
PATHOGEN SYNONYM: Xanthomonas campestris pv. allii
SOURCE: A. Alvarez