DISEASE: Aster yellows
HOST: Watercress
Diseased watercress (left) and healthy plant (right).

Aster yellows | Watercress
DISEASE: Aster yellows
HOST: Watercress (Nasturtium officinale)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: W. Borth
DISEASE: Black rot
HOST: Rutabaga
Rutabaga with discoloration of vascular system.

Black rot | Rutabaga
DISEASE: Black rot
HOST: Rutabaga (Brassica napus var. napobrassica)
PATHOGEN: Xanthomonas campestris pv. campestris
SOURCE: M. Shurtleff
DISEASE: Bois noir disease
HOST: Grape
Infected plant with typical symptoms of rolling, triangular-trapezoid-shaped leaves with desiccated appearance.

Bois noir disease | Grape
DISEASE: Bois noir disease
HOST: Grape (Vitis vinifera 'Pinot Noir')
PATHOGEN: 'Candidatus Phytoplasma solani'
PATHOGEN SYNONYM: Phytoplasma Stolbur group
SOURCE: W. Schweigkofler