Somatic hybridization of an atrazine resistant biotype of Solanum nigrum with Solanum tuberosum : 2. Segregation of plastomes.

Representative regenerated clonal plants from protoplast fusion of Solanum tuberosum L. and an atrazine resistant biotype of S. nigrum L. were studied to ascertain which plastomes each clone contained. DNA was isolated from fractionated chloroplasts, restricted with DNAases XHO-1, BGL-1, PVU-2 and BAM-H1, and the fragments separated by agarose gel electrophoresis for comparison. No difference could be found between resistant and susceptible biotypes of S. nigrum with all four enzymes. XHO-1, BGL-1, BAM-H1 differentiated between S. nigrum and S. tuberosum. All atrazine resistant regenerants, despite plant morphology, had the plastid DNA pattern of S. nigrum while all sensitive ones resembled S. tuberosum, even the subclone 38S having a S. nigrum morphology and chromosome number.