Plant Parasites of Europe

leafminers, galls and fungi

gallers on genus Brachypodium

Dichotomous table for gallers on Brachypodium

by Hans Roskam

1a On inflorescences or flowerd => 7

1b On vegetative plant parts => 2

2a Leaves with long stripes caused by smuts => 6

2b Malformations caused by animal parasites => 3

2c Whitish, at surface yellowish or brownish patches, which envelope a large area of the upper part of stem, of which further development is stunted. Node of stem rarely swollen, encircled by fungus stroma, yellowish when mature; several nodes may be affected; flowering stunted; stroma contains narrow asci and filamentous spores. Brachypodium spp.: Epichloë sylvatica

3a Localised galls on culms => 5

3b Shoot tip with tuft-like clustering of leaves or complete plant disfigured => 4

4a Especially the tips of subterranean runners with short sheath-like, tuft-like accumulated leaves. Gall up to 40 mm long and 12 mm broad. Larva white with black buccal skeleton. B. pinnatum, sylvaticum: Unidentified chloropid fly

4b Tip of above-ground shoot with spindle-shaped tuft of leaves. Inside a larva causing a severely stunted, broadened culm. B. pinnatum, sylvaticum: Tetramesa brachypodii

5a Stem closely just above a node with 10–12 mm long and 4–5 mm broad, saddle-like depression, thickened at both ends, containing a white larva. Usually ± enclosed by leaf sheaths. B. pinnatum, sylvaticum: Mayetiola hellwigi

5b Culm above one of the lower nodes with an egg-shaped swelling about wheat grain size. Containing a single larva. B. sylvaticum: Tetramesa sp.

6a Often all parts of host diseased, exceedingly leafy; initially developing faster, soon severely stunted, remaining small and sterile. Leaves with long, at first slightly arched patches of smut, then breaking open, ± fraying out the leaves, releasing a black-brown mass of spores. B. pinnatum, retusum, rupestre, sylvaticum: Tilletia olida

6b Similar stripes of smut on the leaf blades of often further developed, hardly additionally leafed plants. Spores rotund to oblong-oval, with many blunt warts. B. pinnatum, sylvaticum: Ustilago striiformis

6c Long conspicuous stripes on chlorotic leaf tissue caused by rust fungus. B. pinnatum, sylvaticum: Puccinia striiformis

7a Spikelets elongated; flowers ± greened, bleached if strongly infected. B. pinnatum: Aceria tenuis

7b lowers leafy; glumes ± enlarged, occasionally enclosed in the spikelet; the midrib bent zig-zag-like. B. pinnatum: ? Ditylenchus sp.

7c Complete plant stunted by scale insects, especially the inflorescence. B. pinnatum, retusum, rupestre, sylvaticum: Eriopeltis festucae

Last modified 17.xi.2023