DISEASE: Blossom blast
HOST: Apple
Many dead, shriveled flowers and young shoots. It differs from fire blight, with infections being relatively localized with the appearance of being "blasted".
Blossom blast | Apple
DISEASE: Blossom blast
HOST: Apple (Malus domestica)
PATHOGEN: Pseudomonas syringae pv. syringae
SOURCE: M. Schroth
DISEASE: Larkspur virescence
HOST: Larkspur
Two diseased plants with stunted and small leaves, lack of flower coloration, and bunched flower buds. Healthy plant (left).
Larkspur virescence | Larkspur
DISEASE: Larkspur virescence
HOST: Larkspur (Delphinium sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Raabe
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