Plant Parasites of Europe

leafminers, galls and fungi

gallers on Vinca

Dichotomous table for gallers on Vinca

(incl. Catharanthus)

by Hans Roskam

1a On stems, buds or leaves => 2

1b Roots with nodular to slender spindle-shaped swellings. V. minor: Meloidogyne hapla

2a Malformations of leaves or shoot tips caused by animals => 5

2b Perennial mycelium disfigures complete shoots, which grow with elongated, thinner internodes rigidly erect. Leaves pale green, shortened and thickened; the younger ones curved upwards over their length, keel-shaped. Shoots non-flowering or rarely developing some disfigured flowers => 3

3a Fungi on V. herbacea, minor => 4

3b On V. major: Puccinia vincae

4a On V. herbacea. Infected shoots grow erect, not prostrate like healthy ones, and are etiolated. Leaves distinctly reduced, pale green on underside with many spermogonia and often in lines arranged uredinia and later on ± punctiform telia: Puccinia anatolica

4b Malformations on V. minor similar to fungi occurring on previously reported hosts, but distinguished by lacking uredinia: Puccinia cribrata

5a Malformations caused by aphids => 9

5b Other gall causers => 6

6a Leaf margins loosely rolled inwards or with kidney-shaped swellings. Leaves not conspicuously clustered => 8

6b Buds severely stunted with thickened leaves or top parts of shoots shortened with leaves more clustered => 7

7a Buds severely stunted terminally on end- or side shoots. Between thickened leaf blades of still unfolded buds are several reddish larvae. V. herbacea, major: Dasineura vincae

7b Terminal part of shoot ± shortened. Leaves erupting from buds, more clustered. Leaf blades pod-shaped, often rolled upwards to midrib; lighter, rough, ± bent and twisted. V. herbacea: Aceria liszkai

8a Leaf margin loosely rolled inwards. V. minor: Unidentified psyllid

8b Leaf margin with kidney-shaped swelling. ? V. minor: Inducer unknown

9a Young leaves slightly twisted. Aphid 1.5–2.3 mm long, pale yellow to greenish-yellow, with variable black marks, reminiscent of a horse shoe. V. difformis. major, minor: Aulacorthum circumflexum

9b Malformations may also be caused by Rhopalosiphoninus staphyleae

9c Young leaves severely disfigured, with many pale green or browned spots, resulting from stunting. V. minor: Aulacorthum solani

Last modified 24.iv.2020