Abstract
Nicotiana glauca chloroplasts can be distinguished from N. langsdorffii chloroplasts by a difference in size of the Bam HI restriction endonuclease fragment of chloroplast DNA (ctDNA), and by a difference in the isoelectric focusing pattern of the large subunit of Fraction I proteins. Chloroplast DNA and Fraction I protein were isolated from parasexual hybrid calli derived from cell f usions between N. glauca and N. langsdorffii. Results obtained from 16 calli showed that the expression of the N. glauca type large subunit was correlated with presence of N. glauca ctDNA, N. langsdorffii large subunit with N. langsdorffii ctDNA. Whenever two kinds of ctDNA were present in a callus, both types of large subunit were expressed. Although the Bam HI fragment is distant from the gene for the large subunit, no evidence was obtained for recombination between these two ctDNA markers.
