Abstract
A description is provided for Ustilago hypodytes. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: A wide range of grasses, including species of Agropyron (many), Ammophila, Brachypodium, Bromus, Calamagrostis, Diplachne, Distichlis, Elymus (many), Festuca, Glyceria, Hilaria, Hordeum, Haynaldia, Lygeum, Melica, Orysopsis, Panicum, Phalaris, Phleum, Poa (many), Puccinellia, Secale, Sitanion, Sporobolus, Stipa (many), and Trisetum. DISEASE: Stem smut of grasses. GEOGRAPHICAL DISTRIBUTION: Chiefly a temperate species found in Europe (including Denmark, Finland, France, Germany, Hungary, Italy, Romania, Sweden, Switzerland, UK, USSR, Yugoslavia) and North America (Canada, USA) and extending to central and South America (Argentina, Peru, Uruguay), N. Africa (Libya, Morocco, Tunisia), Japan, Australia and New Zealand. TRANSMISSION: Not fully understood, though inoculation experiments have demonstrated that infection occurs in mature vegetative plants (possibly through meristematic tissue), not seeds or flowers (22, 240; 24, 511). Once established, infection is systemic, probably overwintering in the root system and spreading by vegetative multiplication of host plants as well as from plant to plant (24, 511; 19, 720).