Plant Parasites of Europe

leafminers, galls and fungi

gallers on genus Nasturtium

Dichotomous table for gallers on Nasturtium

(see also Rorippa)

by Hans Roskam

1a Galls on parts above ground => 2

1b Roots conspicuously curved and swollen. N. officinale: Spongospora nasturtii

= The snout beetle Ceutorhynchus assimilis, inducing root collar galls on many crucifers, also occurs on N. officinale, but occasionally without causing galls

= The cyst developing eelworm Heterodera cruciferae has been recorded on Nasturtium

2a Malformations on vegetative organs => 3

2b Flowers swollen, unopened. Corolla stunted, like other parts disfigured and ± thickened. Larvae whitish to lemon-yellow. N. microphyllum, officinale: Contarinia nasturtii

3a Malformations caused by fungi, with fruiting bodies on their surface => 4

3b Axis of young shoots stunted, inserted parts clustered. leaves or leaflets deflected, curled and discoloured deep green close to the froth-covered nymph. N. microphyllum, officinale: Philaenus spumarius

4a Fungus sori dense, at first closed, glossy, porcelain-like, conidia developing in rows, later on with mealy dusting. N. microphyllum, officinale: Albugo candida

4b Fungus fruiting on branched conidiophores, developing in loose down of branched conidiophores. N. officinale: Hyaloperonospora nasturtii-aquatici

Last modified 18.xi.2023