Plant Parasites of Europe

leafminers, galls and fungi

gallers on Reseda

Dichotomous table for gallers on Reseda

by Hans Roskam

1a Malformations on parts above ground => 3

1b Galls on root collar => 2

2a Root collar with weakly globose protruding one-chambered swelling, less than 10 mm long, laterally attached to root as a glabrous gall. R. luteola:
Unidentified snout beetle

= Nodular malformations have been reported on R. luteola, which may be attributed to Meloidogyne hapla

2b Root collar with mainly one-sided, 20–25 mm long, 15–20 mm broad, facultatively originating swellings, soon bearing dying rosette leaves. Containing several larvae. R. luteola: Unidentified snout beetle

3a On inflorescences, shoot tips or leaves => 4

3b Stem with spindle-shaped swelling. R. luteola: Unidentified snout beetle

4a Malformations caused by animal parasites => 5

4b Axial parts of leaves with at first porcelain-white, closed bulges, later on with mealy dusting. R. luteola: Albugo resedae

4c Upperside of the leaf with yellow spots. Underside with a brownish fungal down of erect conidiophores that apically several times are dichotomously branching, each terminal branch ending in an ovoid conidium. R. lutea, luteola: Hyaloperonospora crispula

5a Internodes of stem twisted, ± flattened, strongly curved. Flowers clustered. R. lutea: Unidentified aphid

5b Leaves clustered ± nest-like on severely stunted shoot tips, ± stunted, with several converging, curled, deep green close to the froth-covered nymph. Reseda spp.: Philaenus spumarius

Last modified 31.v.2020