Is rapid flower closure of Drosera effective for defense against herbivores?

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K15154
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 45030:Biodiversity and systematics-related
• Research Institution: Miyazaki International College
• Principal Investigator: Tagawa Kazuki 宮崎国際大学, 教育学部, 准教授 (90830399)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 植物の運動 / 食虫植物 / 誘導防御 / 物理的防御 / モウセンゴケ属

Outline of Final Research Achievements

This study demonstrated that the rapid flower closure of Drosera in response to herbivory is effective as a defense against the specialist herbivore Buckleria paludum caterpillar. Specifically, the following points were revealed: (1) Drosera tokaiensis closed its flowers nine times faster than during natural circadian closure; (2) the flower closure physically hindered the movement of B. paludum into the flowers; (3) the extent of damage to ovules was significantly reduced when the flowers were able to close compared with the condition in which closure was physically inhibited by the application of a resin.

Free Research Field

植物生態学

Academic Significance and Societal Importance of the Research Achievements

一般的に植物は動物と比較してゆっくりと運動する。しかし，中には接触刺激に応答して素早く運動する植物も存在する。このような植物の運動の生態学的意義についてはほとんど分かっていなかった。本研究では，モウセンゴケ属の花閉鎖運動を題材として，植物の素早い運動がスペシャリスト植食者に対する防御効果をもたらすことを初めて定量的に示した。モウセンゴケ属の花閉鎖速度には種間・地域間で変異が存在するため，今後，食害圧と関連した植物の素早い運動の適応進化について，総合的に明らかにできる可能性がある。