DISEASE: Bacterial leaf spot
HOST: Crown-of-thorns
Leaves with brown lesions surrounded by bright yellow halos.
Bacterial leaf spot | Crown-of-thorns
DISEASE: Bacterial leaf spot
HOST: Crown-of-thorns (Euphorbia milii)
PATHOGEN: Xanthomonas axonopodis pv. poinsettiicola
PATHOGEN SYNONYM: Xanthomonas campestris pv. poinsettiicola
SOURCE: APS
DISEASE: Crown gall
HOST: Aspen
Aspen with large, encrusted gall.
Crown gall | Aspen
DISEASE: Crown gall
HOST: Aspen (Populus sp.)
PATHOGEN: Agrobacterium tumefaciens
PATHOGEN SYNONYM: Rhizobium sp.
SOURCE: S. Thomson
DISEASE: Fire blight
HOST: Pear
Blossom blight is first seen as water-soaked spots that rapidly turn brown to black as the disease becomes systemic and progresses down the shoot.
Fire blight | Pear
DISEASE: Fire blight
HOST: Pear (Pyrus communis)
PATHOGEN: Erwinia amylovora
SOURCE: S. Thomson