A cell line of Nicotiana sylvestris with resistance to kanamycin and streptomycin

Cell lines resistant to 50 gg ml- 1 kanamycin sulphate were isolated from cell suspension cultures initiated from a haploid Nicotiana sylvestris plant. One line, KR103, has been studied in detail. Resistance of this line was shown to be stable in the absence of the drug. KR103 was found also to be resistant to streptomycin, another inhibitor of 70S ribosomal protein synthesis. Both KR103 and the sensitive line convert kanamycin, but not streptomycin, to a form which is no longer effective in a bacterial bioassay, while maintaining its toxicity for sensitive plant cells. KR103 is defective in morphogenesis and plastid development