Suggested doses of proton ions and gamma-rays for mutation induction in 20 plant species

Abstract

Purpose

Proton ions are expected to be used as a discriminative radiation source to induce different kinds of mutations than those produced by γ-rays and carbon ions; however, there is little systemic information about radiosensitivity in plants.

Materials and methods

We analyzed the LD₃₀, LD₅₀, and RD₅₀ values in response to proton ions and γ-rays using 20 plant species. Plant seeds were irradiated, and growth responses were measured one month after planting, except for cymbidium, for which in vitro rhizomes were irradiated. The rhizomes were analyzed at six and nine months after subculturing.

Results

Resistance to proton ions and γ-rays was observed in Chinese cabbage, watermelon, and melon, while Japanese atractylodes, naked barley, and lentil were susceptible. Plants belonging to the Brassicaceae and Cucurbitaceae families were highly resistant to radiation, and plants belonging to the Compositae and Poaceae families were highly susceptible. In addition, plants with genome sizes greater than 8,000 Mbp were highly sensitive to radiation, but there was no clear relationship between radiosensitivity and genome size in plants with genomes smaller than 2,500 Mbp.

Conclusions

The biological effectiveness of proton ions was greater than that of γ-rays in 16 plant species, indicating that they could be used as a discriminative radiation source to induce mutations compared with γ-rays.

Keywords:

• Radioresistance
• radiosensitivity
• proton
• gamma-ray
• mutation
• plant

Acknowledgments

The authors thank Dr. Sung Cheol Koo (Department of Herbal Crop Research, NIHHS, RDA, Korea) for providing the seeds of medicinal plants (Japanese atractylodes and licorice).

Disclosure statement

No potential conflicts of interest are reported by the authors. Table 1 has only been used for a noncommercial book, the User’s guideline on proton accelerator for radiation breeding (ISBN 979-11-972905-1-0, in Korean).

Additional information

Funding

This work was supported by a grant from the National Research Foundation of Korea (NRF) funded by the Korean government (MSIP) [2017M2A2A6A05018543].

Notes on contributors

Sang Hoon Kim

Sang Hoon Kim is a Principal Researcher at KAERI. He is working on mutation breeding in horticultural crops.

Sun Young Kim

Sun Young Kim is a Master’s degree student at KAERI. She is working on mutation breeding in oriental orchids.

Jaihyunk Ryu

Jaihyunk Ryu is a Senior Researcher at KAERI. He is working on mutation breeding in medicinal crops.

Yeong Deuk Jo

Yeong Deuk Jo is a Senior Researcher at KAERI. He is working on mutation breeding in pepper and tomato.

Hong-Il Choi

Hong-Il Choi is a Senior Researcher at KAERI. He is working on mutation breeding in rice and medicinal plants.

Jin-Baek Kim

Jin-Baek Kim is a Principal Researcher at KAERI. He is working on mutation breeding in wheat and Arabidopsis.

Si-Yong Kang

Si-Yong Kang was a Principal Researcher at KAERI. He worked on mutation breeding in rice, and was a General Director of the project. He is currently a Professor at Kongju National University.