Diseases and Endophytes
Endophyte infected (E+) grasses show resistance to a few plant diseases caused by fungi. Tall fescue [Lolium arundinaceum (Schreb.) Darbysh.] infected with endophyte (Neotyphodium spp.) is resistant to attack by Rhizoctonia zeae Voorhees. Meadow fescue [Lolium pratense (Huds.) Darbysh. = Festuca Pratensis Huds.] is resistant to R. cerealis Van der Hoeven, Drechslera sorokiniana (Sacc.) Subram. & Jain [= Bipolaris sorokiniana (Sacc.) Shoemaker], and to red thread caused by Laetisaria fuciformis (McAlpine) Burds. Turf fescues, because they are purposely selected to be E+, have been shown to have enhanced resistance to dollar spot caused by Sclerotinia homeocarpa F.T. Bennet. Reports of the severity of rust diseases being reduced by the presence of endophytes in plants are inconsistent. Many strains of rust fungi exist, so it is possible that only some strains are affected by endophyte. However, there are reports of ergot [Claviceps purpurea (Fr.:Fr.) Tul.] being more prevalent in endophyte infected plants than in endophyte free (E−) plants. Insect-transmitted virus diseases of tall fescue and other grasses can be affected indirectly by the presence of endophytes because of compounds produced by the fungus, which deter insect feeding and hence virus transmission. An example of this is the aphid Rhopalosiphum padi (L.), the vector of the barley yellow dwarf virus (BYDV), which is deterred from feeding on E+ tall fescue. Virus infection of endophytes has been reported recently, but the effect of this infection on the endophyte is unknown.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 2009. American Society of Agronomy, Crop Science Society of America, Soil Science Society of America, 5585 Guilford Road, Madison, WI 53711-5801, USA. Tall Fescue for the Twenty-first Century. H.A. Fribourg, D.B. Hannaway, and C.P. West (ed.)