Mutagenic effects of carbon-ion irradiation on dry Arabidopsis thaliana seeds

• A comprehensive Arabidopsis phenotypic mutant collection was constructed.
• Biological effects of carbon ions on Arabidopsis were analyzed.
• The entire set of macroscopic phenotypes induced by carbon ions are shown.
• Carbon ion radiation is an effective mutagen for the generation of various mutants.

To investigate the mutagenic effects of carbon ions on Arabidopsis thaliana (ecotype Columbia) and to isolate useful genes in plant development, dry seeds were exposed to 43 MeV/u carbon ions at doses of 0, 100, 200, 300, 400, 500 and 600 Gy. The survival rate, primary root length, and hypocotyl length of M1 plants were analyzed, and 200 Gy was selected as the dose for the large-scale experiment. A total of 1363 lines of plants from 28,062 M2 populations displayed alterations in the leaf, stem, flower, or life cycle, with abnormal leaves and a premature life cycle as the main phenotypic variations. The mutated gene loci of five stable and inheritable mutations were roughly mapped on chromosomes. Novel mutants were obtained, although some of the mutants were similar to mutants induced by ethylmethane sulfonate (EMS) according to previous studies. This study provides a large body of specific information describing A. thaliana mutation phenotypes that were induced by carbon-ion irradiation. These results suggest that carbon-ion beams are as useful and effective as other mutagens for mutant breeding in plants, and that they will allow mutant breeding that is more diversified.