SELECTION OF ALFALFA CELL-LINES WITH INCREASED PEROXIDASE-ACTIVITY

Efficient doses of the chemical mutagen N-nitroso-N-methylurea and the conditions for obtaining alfalfa (Medicago sativa L.) cell lines with increased peroxidase activity were selected. About one-third of the t ested clones and lines showed enhanced peroxidase activity. When cells were treated with growth-inhibiting doses of the mutagen and then sel ected on media containing 5-methyl-DL-tryptophan, the clones obtained showed the highest peroxidase activity; in the best case, the activity was 2.3 times higher than that in untreated cells. The stimulatory an d inhibitory action of mutagen on suspension growth depended on the do se. Both growth-inhibiting (19-78 mu M h) and growth-promoting (4.9 mu M h) doses of N-nitroso-N-methylurea exerted mutagenesis. The extent of the induction value increased with the mutagen dose.