VIEW ARTICLE

Resistance of St. Augustine Grass to Infection by Sugarcane Mosaic Virus. J. L. Saladini, Former Graduate Assistant, Department of Plant Pathology, University of Florida, Gainesville 32601, Present address of senior author: Department of Plant Pathology, Ohio State University, Columbus 43210; F. W. Zettler, Associate Professor, Department of Plant Pathology, University of Florida, Gainesville 32601. Phytopathology 63:162-166. Accepted for publication 18 August 1972. DOI: 10.1094/Phyto-63-162.

Only 10% of 176 plants of St. Augustine grass inoculated manually with sugarcane mosaic virus (SCMV) became infected, whereas 91% of 114 similarly inoculated corn seedlings became infected. Removal of epicuticular wax deposits with n-butanol prior to inoculations did not materially increase manual transmission rates of SCMV to St. Augustine grass. Low rates of aphid transmission of SCMV to St. Augustine grass were also noted, regardless of the aphid species tested or the virus source plant used. Significant differences in transmission rates were found, however, between two different SCMV isolates from St. Augustine grass. The generally low aphid transmission rates obtained could not be explained by the failure of aphids to probe on leaves of St. Augustine grass. Recorded probe durations were conducive to stylet-borne virus transmission, and aphid stylets were found to be inserted into St. Augustine grass leaf tissue.