Susceptibility of Pearl Millet Accessions and Cultivars to Johnsongrass Mosaic and Sugarcane Mosaic Viruses in Queensland

In 1990, 23 accessions of Pennisetum americanum [P. glaucum] were examined for virus infection at Gatton, south-eastern Queensland, Australia. All accessions had plants with mosaic symptoms. Using sorghum differential test plants, it was shown that Johnsongrass mosaic potyvirus (JGMV) was commonly associated, but 1 isolate of the sabi grass strain of sugarcane mosaic potyvirus (SCMV) was also obtained. In greenhouse tests where 15 accessions of P. americanum were each inoculated with JGMV and the 3 Australian strains of SCMV 17 d after sowing, all 15 were infected by JGMV and the sabi grass strain of SCMV. However, only 2 P. americanum accessions were infected by the Queensland blue couch grass strain of SCMV and 14 with the sugarcane strain of SCMV. JGMV caused an av. of 60% decrease in DM yield 83 d after sowing, whereas strains of SCMV caused less stunting. Australasian Plant Pathology 21(3) 128 - 130 Full text doi:10.1071/APP9920128 © CSIRO 1992