Biological effects of three types of ionizing radiation on creeping bentgrass

Abstract

Purpose: Gamma-rays and carbon ions are frequently used for mutation breeding in diverse plant species, whereas proton ions have been rarely used for this purpose. This study assessed the potential of proton ions for plant mutation breeding.

Materials and methods: We compared the effects of radiation on creeping bentgrass seeds with γ-rays, proton ions, and carbon ions on seed germination, plant growth parameters, and DNA fragmentation.

Results and conclusions: The lethal dose 50 (LD₅₀) doses based on seed germinability were 115.9 Gy (γ-rays), 225.1 Gy (proton ions), and 57.7 Gy (carbon ions). Threshold doses for survival were 150 Gy (γ-rays), 150 Gy (proton ions), and 25 Gy (carbon ions). Suppression of plant growth was displayed at 100 Gy (γ-rays), 25 Gy (proton ions), and 25 Gy (carbon ions). Similar patterns of decreasing head DNA percentage were observed for γ-rays and proton ions. Carbon ions induced the lowest frequency of DNA fragmentation. The biological effects of the ionizing radiation types on creeping bentgrass are summarizable as follows: germination, carbon ions (C)>γ-rays (G)>proton ions (P); survival, C > P = G; growth, C ≥ P > G; DNA fragmentation, G ≥ P > C. These results indicate that proton ions are useful as a physical mutagen in plant mutation breeding.

Keywords:

• γ-rays
• proton ions
• carbon ions
• DNA fragmentation
• creeping bentgrass

Acknowledgements

The authors are especially grateful to Dr. Yoshihiro Hase and Dr. Atsushi Tanaka of the Quantum Beam Science Directorate, Japan Atomic Energy Agency for their help with carbon-ion treatment.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by a National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIP) (2017M2A2A6A05018543) and a grant from the Korea Atomic Energy Research Institute (KAERI), Korea.

Notes on contributors

Sang Hoon Kim

Sang Hoon Kim is Senior Researcher of Korea Atomic Energy Research Institute. He is working on mutation breeding with horticultural crops.

Ye-Sol Kim

Ye-Sol Kim is Researcher of Korea Atomic Energy Research Institute. She is working on mutation breeding with horticultural crops.

Hyo-Jeong Lee

Hyo-Jeong Lee is Researcher of Korea Atomic Energy Research Institute. She is working on mutation breeding with horticultural crops.

Yeong Deuk Jo

Yeong Deuk Jo is Senior Researcher of Korea Atomic Energy Research Institute. He is working on mutation breeding with vegetable crops.

Jin-Baek Kim

Jin-Baek Kim is Principal Researcher and the head of Radiation Breeding Research Team, Korea Atomic Energy Research Institute.

Si-Yong Kang

Si-Yong Kang is Principal Researcher of Korea Atomic Energy Research Institute. He is working on mutation breeding with industrial crops.