RESULTS

(3)

FILTER

DISEASE: Aster yellows

HOST: Squash

Diagnostic characteristics for the disease are yellowing of young leaves, proliferation of secondary shoots, and rigid erect habit. Leaves are misshapen and smaller than normal and have stiff, thick laminae.

Aster yellows | Squash

DISEASE: Aster yellows

HOST: Squash (Cucurbita sp.)

PATHOGEN: 'Candidatus Phytoplasma asteris'

PATHOGEN SYNONYM: Phytoplasma Aster yellows group

SOURCE: S. Miller

DISEASE: Bacterial wilt

HOST: Squash

Field with severe symptoms of wilt. Foliage often is chlorotic and leaf margins may be chlorotic and necrotic before plant death. Bacterial ooze may be seen streaming from the xylem when infected stems are cut.

Bacterial wilt | Squash

DISEASE: Bacterial wilt

HOST: Squash (Cucurbita maxima)

PATHOGEN: Erwinia tracheiphila

SOURCE: B. Jacobsen, M. Shurtleff

DISEASE: Halo blight

HOST: Bean

Leaf of 'Bountiful' bean with chlorotic halos, an early stage of disease. Tiny water-soaked are difficult to see.

Halo blight | Bean

DISEASE: Halo blight

HOST: Bean (Phaseolus vulgaris 'Bountiful')

PATHOGEN: Pseudomonas syringae pv. phaseolicola

PATHOGEN SYNONYM: Pseudomonas savastanoi pv. phaseolicola

SOURCE: M. Schroth