VIEW ARTICLE

Etiology

Grasses Native or Adventive to the United States as New Hosts of Maize Dwarf Mosaic and Sugarcane Mosaic Viruses. Eugen Rosenkranz, Research Plant Pathologist, Agricultural Research Service, U.S. Department of Agriculture and Professor of Plant Pathology, Department of Plant Pathology and Weed Science, Mississippi State University, Mississippi State, MS 39762; Phytopathology 68:175-179. Accepted for publication 7 July 1977. Copyright © 1978 The American Phytopathological Society, 3340 Pilot Knob Road, St. Paul, MN 55121. All rights reserved.. DOI: 10.1094/Phyto-68-175.

One hundred gramineous species, comprising 51 native and 49 adventive grasses, were tested for reaction to inoculation with maize dwarf mosaic virus strains A (MDMV-A) and B (MDMV-B) and sugarcane mosaic virus strain B (SCMV-B). Among these, 57 grasses, belonging to 26 genera, were found to be new hosts of MDMV-A, MDMV-B, and/or SCMV-B. Of the 57 new hosts, 54 were susceptible to MDMV-A, 44 were susceptible to MDMV-B, and 50 were susceptible to SCMV-B. The three virus strains had 42 hosts in common. Most of the common hosts were more susceptible, in terms of disease incidence and severity, to MDMV-A than to MDMV-B or SCMV-B. No differences were found in the host range of the Mississippi and the Ohio isolates of MDMV-A. New host species were found in the following eight genera not previously reported as containing hosts of MDMV or SCMV: Arthraxon, Brachypodium, Hyparrhenia, Leersia, Tragus, Trichachne, Trichloris, and Vaseyochloa. Many of the new grass species are perennial, and some are widely distributed. These could be reservoir hosts of MDMV and SCMV and could thus play a role in the epiphytology of these diseases. Differences in the host ranges of MDMV-A, MDMV-B, and SCMV-B make it possible to propose a set of grasses for identifying and separating these virus strains. Infectivity data indicate that MDMV-B may be more closely related to SCMV-B than is MDMV-A.