Fig. 5. Chloroplast DNA polymorphism among parents and hybrids of switchgrass. DNA was digested with BamHI restriction endonuclease and hybridized with the spinach cpDNA probe pRR12. Lanes A and B are the Summer female and Kanlow male parents, respectively, of the progeny in Lanes C to F. Lanes H and I are the Kanlow female and Summer male parents, respectively, of the progeny in Lanes J to N. Lane O is the Kanlow male parent of the progeny in Lanes P to R. Lane S could not be verified due to death of the source plant. In the last lane on the right the molecular weight of polymorphic bands of HindIII-cut DNA are marked in kilobases (kb).