Development of radioisotope imaging technology of multi-elements in a plant body for agricultural science

• Project/Area Number: 20H04465
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 80040:Quantum beam science-related
• Research Institution: National Institutes for Quantum Science and Technology
• Principal Investigator: Naoki Kawachi 国立研究開発法人量子科学技術研究開発機構, 高崎量子応用研究所 放射線生物応用研究部, 上席研究員 (70414521)
• Co-Investigator(Kenkyū-buntansha): 神谷 富裕 群馬大学, 大学院理工学府, 教授 (70370385)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥17,680,000 (Direct Cost: ¥13,600,000、Indirect Cost: ¥4,080,000); Fiscal Year 2022: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000); Fiscal Year 2021: ¥7,540,000 (Direct Cost: ¥5,800,000、Indirect Cost: ¥1,740,000); Fiscal Year 2020: ¥6,630,000 (Direct Cost: ¥5,100,000、Indirect Cost: ¥1,530,000)
• Keywords: RIイメージング / 元素動態 / 放射線計測 / 放射性同位元素（RI） / 放射線検出器 / コンプトンカメラ / 植物栄養動態 / ラジオアイソトープ

Outline of Research at the Start

植物体内の元素の動きを高精度にイメージングし、その輸送メカニズムを解明することで、新しい作物の創出や栽培技術の革新を可能にしてきた。植物体内の無機元素のほとんどはイオンの形態で存在するため、RIトレーサの利用が適している。しかし、現状では対応可能な種類が限られているため、多様な元素の輸送動態とそれらの拮抗作用の解析は難しい。そこで、撮像可能なRIトレーサ種を増やし、生きたままの植物体内で追跡可能な元素種を増やすとともに、複数RIの同時撮像が可能な植物実験技術を構築する。これを用いて、元素が複雑に絡み合う輸送メカニズムを解明することで、農業の現場が抱える具体的な課題の解決法を導き出す。

Outline of Final Research Achievements

The press release "Rice's Strategy to Survive Drought," based on the results of this research, received a lot of print coverage and attention. Here, we developed a new plant RI imaging technology to investigate underground root function. Using this technology, we have revealed one aspect of the drought tolerance mechanism of rice plants, which involves selective and rapid switching of nutrient partitioning sites in response to humidity conditions. We concluded that this is a powerful tool for elucidating plant survival strategies in detail. Other results included the development of a technique for imaging gas flow in plants to elucidate flood tolerance mechanisms, and results on iron transport dynamics in barley.

Academic Significance and Societal Importance of the Research Achievements

農作物の生産性などを左右する植物が持つ生理機能を探索する強力なツールとして、植物RIイメージング技術を形作った。植物栄養学を基盤とした植物体内の元素の動きを可視化する技術を応用する研究手法の有用性を示すことができた。

Research Products

• [Journal Article] Rice immediately adapts the dynamics of photosynthates translocation to roots in response to changes in soil water environment (2023)
  • Author(s): Miyoshi Yuta、Soma Fumiyuki、Yin Yong-Gen、Suzui Nobuo、Noda Yusaku、Enomoto Kazuyuki、Nagao Yuto、Yamaguchi Mitsutaka、Kawachi Naoki、Yoshida Eiji、Tashima Hideaki、Yamaya Taiga、Kuya Noriyuki、Teramoto Shota、Uga Yusaku
  • Journal Title: Frontiers in Plant Science Volume: 13 Pages: 1024144-1024144
  • DOI: 10.3389/fpls.2022.1024144
  • Peer Reviewed / Open Access
• [Journal Article] Noninvasive imaging of hollow structures and gas movement revealed the gas partial‐pressure‐gradient‐driven long‐distance gas movement in the aerenchyma along the leaf blade to submerged organs in rice (2021)
  • Author(s): Yin Yong‐Gen、Mori Yoshinao、Suzui Nobuo、Kurita Keisuke、Yamaguchi Mitsutaka、Miyoshi Yuta、Nagao Yuto、Ashikari Motoyuki、Nagai Keisuke、Kawachi Naoki
  • Journal Title: New Phytologist Volume: 232 Issue: 5 Pages: 1974-1984
  • DOI: 10.1111/nph.17726
  • Peer Reviewed / Open Access