Plant Parasites of Europe

leafminers, galls and fungi

gallers on Camelina

Dichotomous table for gallers on Camelina

by Hans Roskam

1a On parts above ground => 3

1b On root collar or on roots => 2

2a Root collar with about 6–8 (10) mm long, rotund, often one-sided, succulent, one-chambered galls. Containing a single larva. C. microcarpa, sativa: Ceutorhynchus assimilis

2b Roots with conspicuous spindle-shaped or acuminated, cylindrical, thick fleshy compact swellings of variable size. Camelina spp.: Plasmodiophora brassicae

3a On inflorescences, flowers or fruits => 9

3b On vegetative parts => 4

4a Malformations bearing white fungus sori at surface => 8

4b Malformations caused by animal parasites => 5

5a Inducers inside malformations => 7

5b Leaves on ± stunted shoots clustered, stunted, deflected, sometimes twisted => 6

60a Aphid 2–2.5 mm long, yellowish-green, densely grey powdered. C. alyssum, microcarpa, sativa: Brevicoryne brassicae

6b Aphid 1.5–2 mm long, pale yellowish to yellow-green, not powdered. Camelina spp.: Brachycaudus helichrysi

7a Stems, also leaf axis, with swellings up to about 15 mm long, spindle-shaped. Containing a single larva. C. alyssum, sativa: Ceutorhynchus chalybaeus

7b Stem of young plants severely stunted, spongy, pale green, wrinkled at surface; leaves often considerably stunted, galled from midrib onwards, especially the basal part. Infestation of older plants results in spongy, ± expanded, pale-green, often curved bulges on stems or similar malformations encroaching onto the leaf blades. C. microcarpa, sativa: Ditylenchus dipsaci

8a Fungus sori dense, at first closed, glossy, porcelain-like, later on mealy dusted; their vicinity hardly discoloured, on underside leaf blade rotund, often non-cecidogenic; on midrib and shoot axis elongate oval, often in 2–15 mm long bulges, sometimes curved. Camelina spp.: Albugo candida

8b Malformations expanded, with loose, whitish down of branched conidiophores. Infestation site pale green; on younger leaves often arched upwards. Expanded infestation of young shoots results sometimes in conspicuous thickenings and bendings of stems, as well as to stunting of pale green leaves with margins deflected, slightly thickened and ± brittle. Camelina spp.: Hyaloperonospora camelinae

9a On ± expanded parts of inflorescence or on flowers => 10

9b Silique ± disfigured, soon maturing; inside are several white larvae. C. sativa: Dasineura napi

10a Flowers greened. Axis of inflorescence stunted, sometimes together with neighbouring stem parts. Leaves thickened at margin, rolled downwards, abnormally pubescent. C. microcarpa, sativa: Aceria drabae

10b Inflorescence ± severely stunted, axis sometimes thickened. Flower buds ± densely clustered, swollen. Larvae whitish to pale yellow, jumping. Camelina spp.: Contarinia nasturtii

Last modified 24.viii.2020