Flower color mutants induced by carbon ion beam irradiation of geranium (Pelargonium × hortorum, Bailey)

In an attempt to elucidate the biological effects and underlying mutations involving flower color in ornamental plants following carbon ion beam radiation, shoots of geranium were exposed at dosages of 0, 10, 15, 30, and 40 Gy, and one flower color mutant was obtained. The morphological characteristics, physiological aspects, and DNA polymorphisms between wild-type and flower color mutants were analyzed. The colors of petal, peduncle, pistil, and stamen of the mutant displayed significant differences compared to those of the wild-type. Compared to the original plants, the total anthocyanin content in the petals of the mutant significantly decreased, resulting in a light pink petal phenotype. DNA polymorphisms detected by random amplified polymorphic DNA analysis showed that the ratio of different bands between the wild-type and mutant reached up to 13.2 %. The present study demonstrates that carbon ion beam irradiation is effective in inducing genomic variations, resulting in flower color geranium mutants within a relatively short period of time. Meanwhile, the developed flower-color mutants may be potentially used in future mutational research studies involving ornamental plants.