Plant Parasites of Europe

leafminers, galls and fungi

gallers on Myagrum

Dichotomous table for gallers on Myagrum perfoliatum

by Hans Roskam

1a On parts above ground => 3

1b On roots or root collar => 2

2a About pea-size, ± globular galls on root collar containing a curved beetle larva. Ceutorhynchus assimilis

2b Main- and side roots with conspicuous, spindle-shaped to cylindrical, fleshy galls of variable size. Plasmodiophora brassicae

3a On flowers => 6

3b On vegetative organs => 4

4a Galls caused by animals => 5

4b White bulges on leaves and stems, at first glossy, porcelain-like, later on with mealy dusting. Albugo candida

5a Margins of young leaves bent upwards; leaf blades variously wrinkled or undulate and discoloured pale green. On vegetative shoots several terminal leaves are sometimes accumulated and conspicuously disfigured. Brevicoryne brassicae

5b Terminal leaves or axillary buds clustered; the outer one ± disfigured, at base discoloured and ± thickened, enveloping the bud-like inner leaves. Containing several lemon-yellow, jumping larvae. Contarinia nasturtii

6a Flowers swollen, unopened. Larvae white, non-jumping. Gephyraulus raphanistri

6b Similar galls. Larvae lemon-yellow, jumping. Contarinia nasturtii

Last modified 28.v.2020