The complex viral etiology of St. Augustine decline

St. Augustine decline is a viral disease of St. Augustinegrass, a turfgrass grown in the Gulf Coast region of the United States. Analyses of 204 plant s in two locations in southeast Texas indicate that the disease is caused b y an infection with panicum mosaic virus (PMV), alone or in any combination with satellite panicum mosaic virus (SPMV) and/or its satellite RNAs (satR NAs). This is the first report of the incidence of PMV satRNAs in field sam ples of St. Augustinegrass. Leaf symptoms of plants collected from the fiel d ranged from severe bleaching to a mild chlorotic mottle, but after 5 mont hs in the greenhouse, the plants had a relatively homogeneous chlorotic mot tle phenotype, suggesting that environmental conditions have a significant influence on the development of this disease.