Results of long PCR tests to detect differences in intergenic spacer regions. Here trnfM-CAU to psbD (top), psbD to trnC-GCA (middle) and atpB to rps4 (bottom) are shown. Lengths are calculated from complete plastid genome sequences of Ipomoea purpurea, Cuscuta exaltata and C. obtusiflora are shown beneath genes contained within each region.
McNeal et al. BMC Biology 2007 5:55 doi:10.1186/1741-7007-5-55