NATURAL INFECTION OF PEARL-MILLET AND SORGHUM BY WHEAT STREAK MOSAIC-VIRUS IN KANSAS

Pearl miller (Pennisetum glaucum) and sorghum (Sorghum bicolor) plants at Hays, Kansas, were observed to have viruslike symptoms. Symptomati c plants were tested by enzyme-linked immunosorbent assay (ELISA) agai nst wheat streak mosaic virus (WSMV), maize dwarf mosaic, sugarcane mo saic virus strain MDMV-B, and johnsongrass mosaic virus. Positive reac tions were obtained only with WSMV antisera. Pearl millet and sorghum plants (of genotypes naturally infected in the field) mechanically ino culated in the greenhouse developed symptoms and were positive in ELIS A for WSMV. The virus was vectored by wheat curl mites (Aceria tosiche lla) from pearl millet and sorghum to the host from which it was obtai ned and to wheat. Mechanical inoculation of several sorghum lines show ed that the WSMV isolates differed in ability to infect sorghum, and t he type specimen could not infect any of the sorghum lines. These resu lts indicated that WSMV occurring at Hays can infect sorghum and pearl miller, crop plants not reported previously as susceptible to WSMV.