DISEASE: Apple proliferation
HOST: Apple
Spring form of the adult black-veined psyllid, Cacopsylla melanoneura, a vector of apple proliferation. In winter, adults are more greenish in color.
Apple proliferation | Apple
DISEASE: Apple proliferation
HOST: Apple (Malus domestica)
PATHOGEN: 'Candidatus Phytoplasma mali'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: M. Wolf, W. Schweigkofler
DISEASE: Apple proliferation
HOST: Apple
Typical apple proliferation symptom of witches'-broom resulting from suppression of apical dominance and growth of dormant axillary buds. Branches are not usually bent down as shown here.
Apple proliferation | Apple
DISEASE: Apple proliferation
HOST: Apple (Malus domestica)
PATHOGEN: 'Candidatus Phytoplasma mali'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: M. Wolf, W. Schweigkofler
DISEASE: Aster yellows
HOST: Potato
Chlorotic and stunted foliage with necrotic leaf margins. Other symptoms may be phyllody, virescence, purple or yellow pigmentation, and rolling of leaflets.
Aster yellows | Potato
DISEASE: Aster yellows
HOST: Potato (Solanum tuberosum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson
DISEASE: Aster yellows
HOST: Potato
Stunted, chlorotic plants (left) with stiff, rolled leaves.
Aster yellows | Potato
DISEASE: Aster yellows
HOST: Potato (Solanum tuberosum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson
DISEASE: Aster yellows
HOST: Potato
Diseased plant with malformed tubers.
Aster yellows | Potato
DISEASE: Aster yellows
HOST: Potato (Solanum tuberosum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: S. Thomson
DISEASE: Bacterial decline
HOST: Papaya
Bacterial decline of papaya, historically called St. Croix decline, was thought to be caused by a fungus. This picture shows a papaya with dead top and side branches, a severe stage of the disease.
Bacterial decline | Papaya
DISEASE: Bacterial decline
HOST: Papaya (Carica papaya)
PATHOGEN: Erwinia papayae
SOURCE: M. Schroth
DISEASE: Bacterial decline
HOST: Papaya
Water-soaked papaya stem in St. Croix. Dark, water-soaked, greasy lesions occur on stems and leaves. The causal agent differs somewhat from descriptions of Erwinia papayae D strains in Micronesia.
Bacterial decline | Papaya
DISEASE: Bacterial decline
HOST: Papaya (Carica papaya)
PATHOGEN: Erwinia papayae
SOURCE: M. Schroth
DISEASE: Bacterial decline
HOST: Papaya
Bacterial invasion of leaf veins and adjacent tissues of papaya in Micronesia. This disease has also been called canker, dieback, and blight.
Bacterial decline | Papaya
DISEASE: Bacterial decline
HOST: Papaya (Carica papaya)
PATHOGEN: Erwinia papayae
SOURCE: E. Trujillo
DISEASE: Bacterial decline
HOST: Papaya
Complete destruction of papaya plantation in Micronesia. Only a severely damaged trunk remains.
Bacterial decline | Papaya
DISEASE: Bacterial decline
HOST: Papaya (Carica papaya)
PATHOGEN: Erwinia papayae
SOURCE: E. Trujillo