The functional elucidation of accumulating chemicals on induced resistance in plants: do they contribute to the development of resistance against insects ?

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K06075
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 39050:Insect science-related
• Research Institution: Kochi University
• Principal Investigator: Tebayashi Shinichi 高知大学, 教育研究部自然科学系農学部門, 教授 (70325405)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: ジャスモン酸 / 誘導抵抗性 / スイートピー / ハスモンヨトウ / 摂食阻害 / isoxazolin / サリチル酸 / β-アミノプロピオニトリル

Outline of Final Research Achievements

Through screening examination, it was found that jasmonic acid (JA) treatment of sweet pea (Lathyrus odoratus) can induce resistance against the tobacco cutworm (Spodoptera litura) larvae, as well as indicating that this type of response is relatively universal in the plant-pest-elicitor relationship. Spectroscopic analysis identified 2-cyanoethyl-isoxazolin-5-one (2-CEIX) as the antifeedant with a half-maximal effective concentration of 33.6 µmol/g fr. wt., i.e., exogenous JA treatment induced antifeeding activity due to the accumulation of 2-CEIX. Furthermore, this induced resistance is enhanced by mixing JA with salicylic acid, and that 2-CEIX has insecticidal activity against a wide range of agricultural insect pests. Therefore, 2-CEIX was concluded to be a suitable a target for induced resistance on sweet pea plant or a lead compound for insecticide development.

Free Research Field

化学生態学

Academic Significance and Societal Importance of the Research Achievements

スイートピーにジャスモン酸(JA)を処理することで抵抗性因子（2-CEIX）が誘導蓄積され、それが実際にハスモンヨトウへ抵抗性を示すことを見出すとともに、この種の抵抗性誘導反応は比較的普遍的であることを確認した。これまで実証が脆弱であった誘導蓄積物質が「その濃度で、その植物の害虫に抵抗性を示す」ことを明らかにでき、誘導抵抗性研究のフレームワークを完成に学術的に大きく貢献できた。
さらに、この誘導抵抗性の特性解析や2-CEIXの殺虫スペクトル解析の結果から、リード化合物としての農薬開発や誘導抵抗性型農薬の開発に貢献できることが期待され、社会実装への道が開かれた。