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: Sudden death (Wilt)
HOST: Palm
Palm in Columbia with severe yellowing of leaves.

Sudden death (Wilt) | Palm
DISEASE: Sudden death (Wilt)
HOST: Palm (Elaeis guineensis)
PATHOGEN: Phytomonas sp.
SOURCE: R. McCoy, M. Davis