Mapping the chloroplast genome of triazine resistant canola

The chloroplast of a triazine resistant weed biotype of Brassica campestris (bird's rape) has been transferred by repeated back-crossing into an agriculturally important strain, 'Tower', of Brassica napus to form a triazine resistant cultivar of canola, 'Triton', that is low in both erucic acid and thioglucosinolate. In this report, the B. campestris derived chloroplast chromosome of B. napus (cv 'Triton') has been cloned into bacterial plasmids and physically mapped for eight restriction enzymes: Apa I, Bam HI, BglI, Hind III, Pst I, Pvu II, Sac I and Xho I. The genes for rRNA, rbcL, cytF, atpA, atpB, atpE, atpH and the triazine resistance gene, psbA were located on the map by heterologous hybridization. The directions of transcription for most of these genes were determined by reverse heterologous hybridization.