Eco-evolutionary dynamics in plant-insect interactions

2019 Fiscal Year Final Research Report

• Project/Area Number: 16H04842
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Ecology/Environment
• Research Institution: Kyoto University
• Principal Investigator: Ohgushi Takayuki 京都大学, 生態学研究センター, 名誉教授 (10203746)
• Co-Investigator(Kenkyū-buntansha): 内海 俊介 北海道大学, 北方生物圏フィールド科学センター, 准教授 (10642019)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: 侵入生物 / 生物群集 / 形質進化 / 野外操作実験

Outline of Final Research Achievements

Seasonal growth pattern of tall goldenrod significantly differed among original populations in Japan and the USA. In each experimental garden, plant size of southern populations was significantly larger than northern populations, which was altered by local environment. It suggests that interaction between genetic and abiotic factors is important in determining the plant growth pattern.
Community structure of herbivorous insects largely differed between Japan and the USA gardens. In Japan aphids and lacebugs were more than 90% of overall insect abundance on goldenrod plants, but they were less than 30% in the USA gardens. Although gall-making insects were dominant in the USA gardens, they were not observed in Japanese gardens. It implies that insect-goldenrod interactions and associated insect community have been greatly altered since introduction of tall goldenrod from the USA 100 years ago.

Free Research Field

生態学

Academic Significance and Societal Importance of the Research Achievements

帰化植物の形質と生物間相互作用の研究は世界中で行われているが、原産地との詳細な比較はまだない。本研究から、植物の形質は遺伝的に決まっているが侵入先の生育環境も重要であること、植食者との相互作用は侵入後に大きく変わりうることがわかった。この事実から、植食者群集の激変が植物と昆虫の共進化に大きな影響を与える可能性が示唆された。
また、侵入後の植物形質の遺伝的な維持と生物間相互作用の変化による植物の防衛形質へのフィードバックは、帰化植物に対する被食圧を通しての形質進化が生息地の保全を考える上での新たな課題となることを明確にした。本研究の成果は、このように学術的および社会的に大きな意義をもっている。