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: Pierce's disease
HOST: Grape
Leaves with bright yellow, chlorotic areas with dead, dry, necrotic adjacent tissues.
Pierce's disease | Grape
DISEASE: Pierce's disease
HOST: Grape (Vitis vinifera)
PATHOGEN: Xylella fastidiosa
SOURCE: J. Clark, S. Purcell
DISEASE: Pierce's disease
HOST: Grape
Early symptoms of Pierce's disease on leaves. Symptoms vary greatly among cultivars.
Pierce's disease | Grape
DISEASE: Pierce's disease
HOST: Grape (Vitis vinifera 'Chardonnay')
PATHOGEN: Xylella fastidiosa
SOURCE: J. Clark, S. Purcell
DISEASE: Pierce's disease
HOST: Grape
Late-season wood on diseased canes fail to mature, leaving green "islands" of tissue surrounded by dark brown, mature wood.
Pierce's disease | Grape
DISEASE: Pierce's disease
HOST: Grape (Vitis vinifera 'Fiesta')
PATHOGEN: Xylella fastidiosa
SOURCE: S. Purcell
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
DISEASE: X-disease
HOST: Peach
Early symptoms are reddish, blotchy areas on cupped leaves.
X-disease | Peach
DISEASE: X-disease
HOST: Peach (Prunus persica)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: D. Rosenberger
DISEASE: X-disease
HOST: Peach
Stunted, disfigured peach shoot (left). Healthy (right).
X-disease | Peach
DISEASE: X-disease
HOST: Peach (Prunus persica)
PATHOGEN: 'Candidatus Phytoplasma pruni'
PATHOGEN SYNONYM: Phytoplasma X-disease group
SOURCE: R. Raabe