Elucidation of effects of mild drought stress on plant growth using a newly developed watering system that can precisely control soil moisture

• Project/Area Number: 15K07254
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Science in genetics and breeding
• Research Institution: The University of Tokyo
• Principal Investigator: Todaka Daisuke 東京大学, 大学院農学生命科学研究科(農学部), 特任准教授 (10533995)
• Project Period (FY): 2015-10-21 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000); Fiscal Year 2017: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2016: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2015: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000)
• Keywords: 穏やかな乾燥ストレス / 土壌水分含量制御装置 / 乾燥ストレス / 土壌水分含量 / イネ / 成長

Outline of Final Research Achievements

Drought decreases a plant growth, which leads to a yield reduction. In order to investigate the effects of drought stress on the plant growth, the magnitude of drought stress must be controlled. In this study, a soil matric potential (SMP)-based irrigation system that precisely controls soil moisture was developed. Using this system, rice seedlings were grown under three different drought levels denoted Md1, Md2 and Md3, with SMP values set to -9.8, -31.0, and -309.9 kPa, respectively. Although Md1 did not alter the visible phenotype, Md2 caused shoot growth retardation (SGR). Md3 markedly induced SGR, without photosynthesis inhibition. More severe drought (Sds), under which irrigation was terminated, resulted in leaf wilting and photosynthesis inhibition. Metabolome revealed the sugar accumulation under Md3 and Sds. Transcriptome showed that the expression profiles of associated genes supported the observed changes in photosynthesis and metabolites.

Research Products

• [Journal Article] Temporal and spatial changes in gene expression, metabolite accumulation and phytohormone content in rice seedlings grown under drought stress conditions (2017)
  • Author(s): Todaka D, Zhao Y, Yoshida T, Kudo M, Kidokoro S, Mizoi J, Kodaira KS, Takebayashi Y, Kojima M, Sakakibara H, Toyooka K, Sato M, Fernie AR, Shinozaki K, Yamaguchi-Shinozaki K
  • Journal Title: Plant J. Volume: 90 Issue: 1 Pages: 61-78
  • DOI: 10.1111/tpj.13468
  • Peer Reviewed / Int'l Joint Research
• [Presentation] イネにおける環境ストレス応答性PIF様遺伝子の機能解析 (2018)
  • Author(s): 戸高大輔、橋本貴将、趙宇、篠崎一雄、篠崎和子
  • Organizer: 日本植物生理学会
• [Presentation] Comparative physiological, metabolomic and transcriptomic analyses of rice seedlings grown under different levels of drought stress conditions (2017)
  • Author(s): 戸高大輔
  • Organizer: 日本植物生理学会
  • Place of Presentation: 鹿児島大学（鹿児島県 鹿児島市）
  • Year and Date: 2017-03-17
• [Presentation] 環境ストレス時の生長制御機構の解析 (2016)
  • Author(s): 戸高大輔
  • Organizer: 日本植物生理学会
  • Place of Presentation: 岩手
  • Year and Date: 2016-03-18