Holcus lanatus, België, prov. Antwerpen, Geel, Neerhelst © Carina Van Steenwinkel

conidium

gall

Infected plants often are severely disturbed in their development.

host plants

Poaceae, oligophagous

Agrostis; Alopecurus; Arrhenatherum; Avena; Calamagrostis; Dactylis; Holcus mollis; Phalaris; Phleum; Poa; Trisetum; Triticum.

synonyms

Dilophia graminis (Fuckel) Saccardo,1993; Lidophia graminis (Saccardo) Walker & Sutton, 1974. Both are names of the supposed teleomorph.

notes

Dilophospora alopecuri lives on a wide range of grasses, including cereals. The species is distributed by conidia, and is able to infect plants directly, which leads to localized infections in the form of leaf spots. The conidia have at both ends specialised structures that enable them to attach to fine grooves in the epidermis of nematodes of the genera Anguina and Subanguina, like Anguina graminis and Subanguina graminophila. These nematodes live endobiotically in grasses, causing characteristic growth disturbances. Only conidia adhering to these nematodes can penetrate the growing tissue and develop into systemic mycelium. The mycelium can enter the developing seeds, leading to vertical transmission. Once systemic, the mycelium has a strongly deleterious effect on the nematodes.

In some subtropical regions the nematodes also carry a poisonous bacterium, viz., Clavibacter toxicus. Some grasses, in particular Lolium rigidum, can become toxic to such an extent that massive cattle mortality may result. For this reason the particular grass was rigorously controlled, but presently the problem is handled by spraying an emulsion of D. alopecuri conidia.

references

Asad, Sultan, Iftikhar, Munir, Ahmad & Ayub (2007a), Bird & McKay (1987a), Brandenburger (1975a: 798), Buhr (1964b), Ellis & Ellis (1997), Mäkelä & Koponen (1975a), Norton, Cody & Gabel (1987a), Rainio (1936a), Riley & McKaay (1990a).