ISSR analysis of cymbidium 'longchangsu' seedlings in vitro and mutagenic progenies by radiation

Inter-Simple Sequence Repeat (ISSR) molecular markers were used to analyze the Cymbidium 'longchangsu' seedlings in vitro, mutagenic progenies and the leaf shape mutants by ⁶⁰Co γ rays. Results showed that the differentiation rate of the radiated rhizomes by 10 Gy and 20 Gy were 93.2% and 54.4%, respectively. The rhizomes radiated by 40 Gy and 60 Gy were all died. The mutation rates of seedlings by repeatedly subcultured in vitro were 6% and the mutagenic progenies by radiation were 18%. It is indicated that the mutagenic rates caused by radiation is higher than that by tissue culture. No significant differences were observed between suspicious mutants and the control after the gene detection of the leaf shape mutants. It suggests that, maybe, there were not significant correlation between ISSR results and the morphological changes. (authors)