Does the increase in leaf thickness to drought contribute to xylem cavitation resistance in leaves?

2015 Fiscal Year Final Research Report

• Project/Area Number: 26660125
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Forest science
• Research Institution: Kyoto University
• Principal Investigator: Ishida Atsushi 京都大学, 生態学研究センター, 教授 (60343787)
• Co-Investigator(Kenkyū-buntansha): SANO Yuzou 北海道大学, (連合)農学研究科(研究院), 教授 (90226043)
• Research Collaborator: SAIKI Shin-Taro ; YOSHIMURA Kenichi ; YAZAKI Kenichi ; NAKANO Takashi
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 乾燥耐性 / 小笠原 / 道管 / 壁孔壁 / キャビテーション耐性 / 水ポテンシャル / 通水性 / 葉厚

Outline of Final Research Achievements

On the Ogasawara islands, there are slopes from dry ridge to wet valley. Along the slopes, we examined the relationships between the vulnerability of leaf xylem and leaf thickness in the sun leaves of Hibiscus glaber. Towards the dry ridge, the leaf thickness increased in spite of a constant light condition. However, the vulnerability of leaf xylem remained constant. The data indicate that the increase in leaf thickness is related to an increase in leaf capacitance, rather than cavitation tolerance in xylem, contributing to a maintenance of leaf turgor and water content against temporary leaf dehydration. Among woody plants growing at the dry ridge, micropores in intervascular pit membranes in branchelets are consistently small, indicating high cavitation tolerance. To date, xylem anatomy has been considered as species or genera specific, but we first capture the clue of the co-evolutionary variations between physiology and xylem anatomy.

Free Research Field

樹木生理生態