Stability of the PDS insert in the BMVF13m or BMVCP5 vector during infection in maize. Virion RNA was isolated from BMVF13m:PDS (F13m:PDS)- or BMVCP5:PDS (CP5:PDS)-inoculated leaves harvested at 5 dpi or from the second systemically infected leaves harvested at 7 dpi and used for RT-PCR. Three maize plants were used for each treatment, PCR products from the same treatment were gel purified, pooled, and cloned, and plasmids were sequenced for the presence of insert. The top diagram illustrates the RNA3 3′ sequence organization in the BMV vectors. The black lines and numbers in the far left column under the diagram show the lengths of retained PDS sequences in the progeny virus populations from the pooled samples for each treatment (250 nucleotides representing the full-length insert). #, Values in the table represent the number of clones from each treatment containing a particular length of insert; *, the total number of clones sequenced for the treatment. UTR, Untranslated region.