Plant Parasites of Europe

leafminers, galls and fungi

gallers on Isopyrum

Dichotomous table for gallers on Isopyrum thalictroides

(incl. Leptopyrum fumarioides.)

by Hans Roskam

1a Expanded galls caused by rust fungi which fruit on the outside => 2

1b Wart-shaped, pearl-like gall consisting of only a few cells on leaves and stems. Sporangia colourless, with a nutritive cell inside. Synchytrium anomalum

2a Swellings bearing yellow aecia => 3

2b Swellings and malformations, up to 1 cm long, on stems, petioles and leaf veins with fungus developing only black, normally 3-celled teliospores, with dusty sori. Triphragmiopsis isopyri

3a Aecia on Leptopyrum fumarioides:

a Aecia golden-yellow, usually on distinct bulges on underside of veins, midrib or stalk of leaves. Puccinia actaeae-elymi

b Galls similar. Aeciospores narrow fine-warty. Outer wall of peridium 6–7 μm thick, transversely striate; inner wall coarse warty, 2–3 μm thick. Fungus alternating to wheat and related grasses. Puccinia recondita

3b Thickened bulges on the leaf axis and leaf blade. Puccinia milii-effusi

Last modified 7.vii.2020