Smut, Leaf smut, Blackish areas on leaves Stripped or Flag Ustilago spp. Moist, humid warm weather. may be rubbed off with smut. fingers. Circular dead first appear in spring. The spots appear in many of the same places and expand for 3 to 4 Leptosphaeria narmari Spring dead spot years. After the second or and L. korrae third year, the disease often appears as rings of dead grass, and may disappear after 3 or 4 more years. Patch of bronzed or Common to newly established bleached turf 10-15 cm turfs, diminishing with the build diameter grows to 1 m over Gaeumannomyces Take all patch up of antagonistic a period of years. Black graminis microorganisms in soil. runner hyphae can be seen Favours high pH. under base of leaf sheath, on crowns and roots. 8 – Common Environmental Scientific Name Hosts Symptoms/Damage Name Factors Barley Reductions in establishment, yellow dwarf Perennial competitiveness, persistence, virus ryegrass productivity and pasture quality (BYDV) (Clarke and Eagling, 1994). Extended periods of leaf wetness in Seed heads. Infection usually late results in seed death. Seed from Blind seed Perennial November/early Gloeotinia granigena heavily infected stands has reduced disease ryegrass December and air commercial value because of poor temperatures of germination rates (Vargas, 2005). 1525°C favour the highest incidence. Drechslera siccans Perennial The leaf-spot, Small brown spots which enlarge Brown blight (syn. ryegrass, and root rot and may develop white centres
Smut, Leaf smut, Stripped or Flag smut. Ustilago spp. Moist, humid warm weather. Blackish areas on leaves may be rubbed off with fingers. Spring dead spot Leptosphaeria narmari and L. korrae Circular dead first appear in spring. The spots appear in many of the same places and expand for 3 to 4 years. After the second or third year, the disease often appears as rings of dead grass, and may disappear after 3 or 4 more years. Take all patch Gaeumannomyces graminis Common to newly established turfs, diminishing with the build up of antagonistic microorganisms in soil. Favours high pH. Patch of bronzed or bleached turf 10-15 cm diameter grows to 1 m over a period of years. Black runner hyphae can be seen under base of leaf sheath, on crowns and roots. 8 – Common Name Scientific Name Hosts Environmental Factors Symptoms/Damage Barley yellow dwarf virus (BYDV) Perennial ryegrass Reductions in establishment, competitiveness, persistence, productivity and pasture quality (Clarke and Eagling, 1994). Blind seed disease Gloeotinia granigena Perennial ryegrass Extended periods of leaf wetness in late November/early December and air temperatures of 1525°C favour the highest incidence. Seed heads. Infection usually results in seed death. Seed from heavily infected stands has reduced commercial value because of poor germination rates (Vargas, 2005). Brown blight Drechslera siccans (syn. Perennial ryegrass, The leaf-spot, and root rot Small brown spots which enlarge and may develop white centres
The%20Biology%20of%20Ryegrass%20and%20Tall%20fescue%202017.docx