Stable maintenance of foreign DNA in transformed cell lines of rice (Oryza sativa L.).

Abstract
Intensive studies were carried out to rule out the integration manner of foreign DNA in the genome of transformed cell lines of rice (Oryza sativa L.), which had been obtained from protoplasts treated with bacterial plasmids. A common portion (>ca. 7 kbp) of the vector, pCT2T3 (18.3 kbp) containing two marker genes; a chimeric kanamycin resistant gene and nopaline synthase gene was detected in two transformed cell lines. Stable maintenance of inserted DNA was demonstrated in one year-old cells kept in either selective or non-selective medium.