Plant Parasites of Europe

leafminers, galls and fungi

gallers on Carum

Dichotomous table for gallers on Carum

(inc. Bunium)

by Hans Roskam

1a On parts above ground => 2

1b Roots with nodular swellings. C. carvi: Meloidogyne hapla

2a On inflorescences, flowers or fruits => 12

2b On vegetative parts => 3

3a Galls bulging, bearing aecia on surface => 11

3b Aecia absent, differently shaped => 4

4a Galls caused by animal inducers or by fungi, fruiting inside => 5

4b Basal leaves variously disfigured. Leaf blades ± arched, soon with expanded areas of grey-white asci. C. carvi: Taphridium umbelliferarum

5a Malformations extended over large parts of leaves => 9

5b Malformations of various expansions on leaf-axis or leaf veins, hardly 1 mm across, wart-shaped => 6

6a Swelling of axis, usually ± exceeding 2 mm => 8

6b Galls ± hemispherical, wart-shaped, usually on leaf underside, on midrib and stalk; sometimes coalesced into smaller ridges or crusts. Perennial spores only in a central strongly swollen nutritive cell surrounded by enlarged auxiliary cells => 7

7a Galls distinctly golden-yellow translucent. C. carvi: Synchytrium aureum

7b Warts very similar, glass clear, later on dark coloured, bead-like; also observed close to umbel. C. carvi: Physoderma hemisphaericum

8a Compact, glabrous, pale green, vitreous, spindle-shaped bulges, about 2–15 mm long on leaf veins and midrib, -stalk and young stem. Many spores close to vascular bundle. C. carvi: Protomyces macrosporus

8b Stalk and midrib ± severely stunted and spongy, swollen. Galls yellow-green, soft, wrinkled at surface, usually over large expansion at lower stem parts and basal leaves; sometimes also as localised bulge on leaf midrib as well as on stem. C. carvi, verticillatum: Ditylenchus dipsaci

9a Leaf blade curled, caused by aphids or cercopids => 10

9b Tip of leaf broadened, thickened, shortened and deflected or enlarged and lacerate; sometimes clustered bush-like due to stunting of midrib. C. carvi: Aceria carvi

10a Leaves converging downwards ± nest-like; curled and deep green close to the froth-covered nymph. Carum spp.: Philaenus spumarius

10b Leaves slightly curled and discoloured, often initially etiolated. Aphid pale green, with bifid cauda. C. carvi: Cavariella aegopodii

11a Leaf veins, -midrib, -stalk or also stem with bulges bearing yellowish spermogonia and aecia. Aecia pustule-shaped, with round exit hole. C. carvi: Puccinia bistortae

11b Only aecia formed, these cup-shaped, with frayed, whitish border. C. carvi: Puccinia polygoni-alpini

12a On inflorescences or flowers => 13

12b Fruit bladder-like swollen, often ± reddened, protruding above the umbel. Containing 1 (‒3) orange-red larvae. C. carvi, verticillatum: Kiefferia pericarpiicola

13a Malformations on expanded parts of umbel => 14

13b Stalks at centre or close to (partial) umbel ± swollen club-shaped or globular. Galls one-, also multi-chambered. Inner wall with mycelium. Each chamber contains a single larva. C. carvi, verticillatum: Lasioptera carophila

14a Inflorescence variously stunted and tangled, flowers stunted => 15

14b Inflorescence severely disfigured. Many parts of flowers leafy, corolla sometimes greened, also discoloured whitish-green or reddish. C. carvi: Aceria carvi

15a Stalks of young inflorescence variously stunted, also distorted. (Partial) umbels ± tangled. Flowers stunted and disfigured. Contain froth-covered nymph. Carum spp.: Philaenus spumarius

15b Similar malformations on young inflorescence caused by many aphids. C. carvi: Hyadaphis foeniculi

Last modified 6.iv.2020