Role of xylem parenchyma cells in water conduction and defense mechanism of trees

2019 Fiscal Year Final Research Report

• Project/Area Number: 16H04936
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Forest science
• Research Institution: Kobe University
• Principal Investigator: Kuroda Keiko 神戸大学, 農学研究科, 教授 (20353675)
• Co-Investigator(Kenkyū-buntansha): 石井 弘明 神戸大学, 農学研究科, 准教授 (50346251) ; 黒田 克史 国立研究開発法人森林研究・整備機構, 森林総合研究所, 主任研究員 等 (90399379) ; 東 若菜 京都大学, 農学研究科, 特別研究員(PD) (20780761)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 水分通導 / エンボリズム / 木部細胞 / 通水回復 / 柔細胞 / 二次代謝 / 乾燥耐性 / 物質移動

Outline of Final Research Achievements

Water-stressed and temporally embolized xylem recovered water conduction by the water supply via parenchyma cells in Cinnamomum camphora, or via narrow vessels in a liana species, Wisteria japonica. The rehydration system will contribute the drought resistance of these species. The transfer of substances between parenchyma and water conduits was demonstrated by the injection of living tissue with cesium solution.
Averaged vessel diameter near the base of aged C. camphora was larger than that at the top of trees. Large vessels efficiently transport water to a whole tree. On the other hand, at the upper part, the wider latewood with narrow vessels will physically strengthen the stem. Water content of leaves of Cryptomeria japonica was higher in the upper shoots. Near-infrared spectroscopy with a mobile apparatus enabled the measurement of pigment concentration ascribable to the differences in mesophyll structure.

Free Research Field

樹木生理学

Academic Significance and Societal Importance of the Research Achievements

樹木の乾燥耐性や木部内の物質移動に関する細胞学的データや，老齢木の通水・保水に関わる生理学的データなど、学術的に重要な基礎的知見を得た。それらの知見をもとにして、森林や緑化木の維持にあたって必要な対策をとることができる。都市的環境下において、近年は気温上昇や乾燥による樹木の衰弱が起こりやすく、また、老齢樹の維持管理が求められるており、その現場に役立てることができる。