Dynamic Optimization by Endogenous and Exogenous Programs in Plant Structural System Formation

2022 Fiscal Year Final Research Report

• Project Area: Elucidation of the strategies of mechanical optimization in plants toward the establishment of the bases for sustainable structure system
• Project/Area Number: 18H05487
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Complex systems
• Research Institution: Kumamoto University
• Principal Investigator: Sawa Shinichiro 熊本大学, 大学院先端科学研究部(理), 教授 (00315748)
• Co-Investigator(Kenkyū-buntansha): Ferjani Ali 東京学芸大学, 教育学部, 准教授 (20530380)
• Project Period (FY): 2018-06-29 – 2023-03-31
• Keywords: 機械的刺激 / 力学的最適化 / 植物構造システム

Outline of Final Research Achievements

In this study, we aimed to understand how plants receive mechanical stimuli, how they are converted into chemical signals, and how they output to phyto -plastogenesis as a system, and to clarify the whole picture.
As a result, it was confirmed that in both stems and root systems, the epidermis functions as a hoop, and its physical constraint regulates the internal cell division activity, and the physical pressure acts as a signal to maintain the internal structure to prevent cracks in the stem. Genes involved in this phenomenon were also identified in stems and roots. Furthermore, we constructed a 3D structural observation system for roots in soil using X-ray CT scans, and clarified the correlation between the force of roots sticking to the ground and the root system structure in soil.

Free Research Field

植物分子形態学

Academic Significance and Societal Importance of the Research Achievements

重力や機械刺激、または内生発生プログラムによって生じた局所的なシグナルが植物の器官・個体レベルでの成長を制御する分子機構は、これまでほとんどわかっていなかった。本研究では、「機械刺激が関わる植物の放射軸形成機構、及び根系形成のシステムの理解を目指す」という、これまでに類を見ない、全く新しい研究を行った。目に見えない機械刺激をテーマに、張力測定のような、新たな研究手法の確立から行った。どのように機械刺激が植物の内生発生プログラムを制御するのかを明らかにしたことから、植物生理学の新たな局面を迎えることができたと考えている。