DISEASE: Marginal leaf blight
HOST: Lettuce
Marginal leaf blight first appears as slimy wilting of leaf margins. Small, reddish lesions may be seen on leaf blades. Infected tissues turn brown to black in time.

Marginal leaf blight | Lettuce
DISEASE: Marginal leaf blight
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Pseudomonas marginalis
SOURCE: L. Fucikovsky
DISEASE: Purple stain
HOST: Papaya
Purple pigmentation of internal tissues near peduncle end of fruits. Pigmentation and yellow translucence of papaya flesh are more evident of fruit on right.

Purple stain | Papaya
DISEASE: Purple stain
HOST: Papaya (Carica papaya)
PATHOGEN: Pantoea agglomerans
PATHOGEN SYNONYM: Erwinia herbicola
SOURCE: M. Nelson
DISEASE: Purple stain
HOST: Papaya
Purple pigmentation of internal tissues.

Purple stain | Papaya
DISEASE: Purple stain
HOST: Papaya (Carica papaya)
PATHOGEN: Pantoea agglomerans
PATHOGEN SYNONYM: Erwinia herbicola
SOURCE: M. Nelson
DISEASE: Purple stain
HOST: Papaya
Another view of purple discoloration at peduncle end. Bacteria are found in vascular tissues and latex ducts.

Purple stain | Papaya
DISEASE: Purple stain
HOST: Papaya (Carica papaya)
PATHOGEN: Pantoea agglomerans
PATHOGEN SYNONYM: Erwinia herbicola
SOURCE: K. Nishijima
DISEASE: Purple stain
HOST: Papaya
Cross section of fruit exhibiting purplish discoloration in latex ducts.

Purple stain | Papaya
DISEASE: Purple stain
HOST: Papaya (Carica papaya)
PATHOGEN: Pantoea agglomerans
PATHOGEN SYNONYM: Erwinia herbicola
SOURCE: M. Nelson, A. Alvarez
DISEASE: X-disease
HOST: Peach
Typical symptoms of diseased tree with yellowing of leaves. Leaves become necrotic and dehisce.

X-disease | Peach
DISEASE: X-disease
HOST: Peach (Prunus persica)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: R. Davis, M. Davis
DISEASE: X-disease
HOST: Peach
Late stage of leaf infection. Red-yellow blotches appear after initial water-soaking of leaves. Margins roll upward and leaves appear tattered.

X-disease | Peach
DISEASE: X-disease
HOST: Peach (Prunus persica)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: W. Sinclair
DISEASE: X-disease
HOST: Peach
Stunted foliage (left) with some necrosis and small angular fruit. Healthy foliage and fruit (right).

X-disease | Peach
DISEASE: X-disease
HOST: Peach (Prunus persica)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: A. Purcell, M. Davis