Plant Parasites of Europe

leafminers, galls and fungi

gallers on Plantago

Dichotomous table for gallers on Plantago

by Hans Roskam

1a Malformations on parts above ground => 2

1b Side roots often with many, nodular or spindle-shaped swellings bearing some side roots. P. lanceolata, major, media: Meloidogyne hapla

2a On inflorescences, flowers or fruits => 13

2b On leaves or scape of inflorescence => 3

3a Mainly on leaf blades => 7

3b Mainly on scape of inflorescence, occasionally on root collar, on petioles, rarely on main veins => 4

4a Inducers inside the galls => 5

4b Scape of inflorescence, rarely also the more slender parts of petiole, with broad elliptical, usually buckled swellings, with rimmed depression on concave side containing a froth-covered nymph covered by a scale. Galls sometimes coalescing, tuberculate-bulging, ± curved swellings with several nymphs on lower situated parts of scape. P. lanceolata: Planchonia arabidis

5a Galls distinct => 6

5b Weak swelling of stem. P. lanceolata: Mecinus labilis

6a Conspicuous, 10‒20 mm long, up to 3 mm thick, spindle-shaped, tough-walled swellings usually in upper part of scape, also encroaching into the axis of the inflorescence; exceptionally also in petioles. Pith containing a curved weevil larva. P. altissima, coronopus, holosteum, lanceolata, major, maritima, media: Mecinus collaris

6b Similar, up to 10 mm long, 3 mm thick spindle-shaped galls on P. lanceolata, rarer on P. media: Mecinus pyraster

= From P. coronopus, lanceolata, maritima the weevil Mecinus circulatus has been recorded

7a Leaf blades with expanded malformations => 8

7b Many warts on leaf blades, less than 1 mm long, sometimes ± crust- or ridge-like, coalescing, multicellular; occasionally encroaching onto petioles and scape. P. alpina, arenaria, lanceolata, major, “psyllium”: Synchytrium aureum

8a Leaf blade variously folded, curled, rolled or with open bladder-like swellings => 9

8b Leaf blade stunted, with closed, localised or expanded, pale-green, occasionally reddened on upperside, spongy, especially swellings situated on venation. P. lanceolata, maritima, rarely on P. major, media: Ditylenchus dipsaci

9a Malformations without abnormal pubescence => 10

9b Leaf margin narrowly rolled upwards; roll ± distorted and abnormally pubescent; leaf blade ± wrinkled. P. lanceolata: Unidentified gall mite

10a Minor bulges or loose curls of parts of leaf blade, without distinct malformation of venation => 12

10b Malformation includes leaf veins => 11

11a Leaf blade folded along the ± curved midrib, thickened, irregular transversely wrinkled. P. altissima, lanceolata, major, media: Leipothrix coactus

11b Leaf blades deflected over their top, locally undulately curled and deep green; at margin ± curved downwards. Shoots stunted in narrow-leafed species, leaves ± clustered, nest-like. Plantago spp.: Philaenus spumarius

12a Leaf blade with minor upward archings, yellow-green, up to 15 mm broad; with dirty violet down of branched conidiophores on underside. Parts bearing oospores often more thickened. Leaves on systemically infected plants longer stalked, erect, leaf blades bleached and narrowed. Plantago spp.: Peronospora alta

12b Leaf blade shortened and variously contracted. P. major: Unidentified aphid

13a Inflorescences or flowers with abnormal pubescence, hypertrophied and eventually becoming tough. P. albicans, ceratophylla, commutata, coronopus, serraria: Aceria barroisi

13b Fruit slightly swollen, ± conical, tip acuminate, shorter than healthy fruits. Between the fruits live orange-red larvae. P. lanceolata, major, maritima, media: Jaapiella schmidti

13c One to several fruits remain small, disfigured, browned. P. lanceolata: Gibberella fujikuroi var. subglutinans

Last modified 24.viii.2020