FIG 4.

PMV, SPMV, and satC RNAs are polyadenylated during natural infections of St. Augustinegrass. (Top) Three asymptomatic (A1 to A3) and symptomatic (S1 to S3) St. Augustinegrass leaf samples were collected from the Texas A&M University campus. Symptomatic samples were selected based on the typical chlorotic mottling associated with PMV infection and St. Augustine decline disease. (Bottom) Semiquanititative RT-PCR detection of PMV, SPMV, and satC cDNA from mRNA-enriched RNA purified from the six St. Augustinegrass tissue samples. Sample cDNAs were synthesized using oligo(dT) primers for reverse transcription. Primers for the PMV capsid protein ORF (PMV-CP), the SPMV capsid protein ORF (SPCP), and satC were used for amplification of PMV, SPMV, and satC cDNAs, respectively (see Table S2 in the supplemental material). Lane +, PCR mixtures containing the PMV, SPMV, or satC infectious cDNAs as positive controls for amplification.