Plant Parasites of Europe

leafminers, galls and fungi

gallers on Crambe

Dichotomous table for gallers on Crambe

by Hans Roskam

1a On leaves and stems => 3

1b On roots or on root collar => 2

2a Roots with conspicuous spindle-shaped or acuminated, cylindrical succulent, compact swellings. C. abyssinica, maritima, tataria: Plasmodiophora brassicae

2b Rotund, about pea-size, one-chambered galls on root collar. Containing a single larva. C. maritima: Ceutorhynchus assimilis

3a Expanded malformations caused by aphids => 5

3b Galls of lesser expansion, ± pad- or bulge-shaped => 4

4a Galls spindle-shaped, 15‒20 mm long, also green inside, on petioles, leaf veins or thinner stems. Containing a single larva. C. abyssinica, maritima, tataria: Ceutorhynchus chalybaeus

4b At first closed glossy, porcelain-like, later on rupturing and with mealy dusting, rotund to oblong-oval pads or bulges on leaves, stems and stalks of inflorescences. C. maritima, tataria: Albugo candida

4c Stem and also axis of inflorescence usually with expanded, conspicuous, often distorted swellings, soon covered with a down of branched conidiophores. Flowers of diseased inflorescences severely stunted. Leaves of axillary shoots if infected early, ± spoon-like arched, thickened, brittle, pale green; with a dense down of conidiophores on underside. C. maritima, tataria: Hyaloperonospora parasitica

5a Complete plant disfigured, leaves rolled, flowers greened. C. maritima: Lipaphis hedickei

5b Leaf blades of basal leaves with irregular paler green, sometimes ± red-violet marbled archings. C. abyssinica, maritima: Brevicoryne brassicae

Last modified 12.ix.2020