Altitudinal variation in leaf out phenology and its evolutionary response to climate change in Fagus crenata populations

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K05737
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 40010:Forest science-related
• Research Institution: Hirosaki University
• Principal Investigator: Ishida Kiyoshi 弘前大学, 農学生命科学部, 教授 (10343790)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 開葉フェノロジー / 開芽積算温度 / 晩霜 / 消雪日 / 集団間変異 / 表現型可塑性 / 遺伝的変異 / 気候温暖化

Outline of Final Research Achievements

We studied local variations and phenotypic plasticity in leaf out phenology of Fagus crenata populations in the Hakkoda mountains, Aomori prefecture, on the basis of field survey at multiple areas with different altitudes and topographies. We revealed that observed local variation was related to the late frost regimes and the day of snow-melting. We also found that the temperature sum of budburst and that of leaf expansion correlated with the chilling days (chilling duration during autumn to spring before leaf out) and that the extent of phenotypic plasticity of the temperature sum differed between populations with different topographies. In plantation experiments, we observed that the day of budburst od seedlings differed between provenances with different altitudes and late frost regimes, indicating genetic variation along altitude and topographies. In addition, we suggested that the extent of phenological response to climate warming would differ between populations.

Free Research Field

森林生態学

Academic Significance and Societal Importance of the Research Achievements

自然集団を対象とした観測により明らかにしたブナの開芽時期の標高・地形間変異と表現型可塑性についての知見は、今後の気候温暖化に伴ってブナ集団の春の季節性が短期的にどのように変化するのかを予測することに貢献する。また、標高別植栽試験によって明らかにしたブナの開芽日における表現型可塑性の遺伝的変異は、気候温暖化に伴う集団の進化的応答（次世代における開芽日の変化）の予測の基礎となる。環境変化に対する樹木集団の進化的応答のポテンシャルを推定した研究事例は少なく、本研究の成果は環境変動に対する樹木の適応可能性についての理解の深化に貢献するものといえる。