Molecular basis of activation of plant immune system by atomasphic plasma irradiation and its application to plant disease control

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K14858
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Plant protection science
• Research Institution: Tohoku University
• Principal Investigator: Takahashi Hideki 東北大学, 農学研究科, 教授 (20197164)
• Co-Investigator(Kenkyū-buntansha): 金子 俊郎 東北大学, 工学研究科, 教授 (30312599)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: 大気圧プラズマ / 植物病原体 / 活性酸素種 / 活性窒素種 / 植物病害防除

Outline of Final Research Achievements

When rice seeds were irradiated with atmospheric plasma, the occurrence of "Bakanae disease" and bacterial damping-off disease in rice seedlings was suppressed. Irradiation of Arabidopsis thaliana with plasma reduced the level of virus multiplication. It has been known that reactive oxygen species act as a signaling molecule for plant immune system. Interestingly, the comprehensive analysis of reactive molecules produced by atmospheric plasma irradiation indicated that peroxynitrite (HOONO) and pernitric acid (HOONO2), which have antimicrobial activity, and N2O5 accumulated in gas phase, and NO3- was detected in liquid phase. Furthermore, in plants irradiated with atmospheric plasma, defense-related gene expression: PR1, PDF1.2 and ChiB, was significantly induced, suggesting that plant immune system seems to be activated by irradiation of plants with atmospheric plasma.

Free Research Field

植物病理学

Academic Significance and Societal Importance of the Research Achievements

プラズマを植物種子や葉に照射することにより、殺菌作用や植物免疫を介して病気の発生を抑制できることが明らかになった。これらの知見は、プラズマを活用することにより、農薬のみに依存しない病害防除と安全・安心な農産物の生産の実現や、農薬の使用を削減することによる環境保全への貢献が期待できる。
さらに、プラズマ照射により生成される活性分子種が明らかになったことは、プラズマ照射が植物の生育に及ぼす影響（効果）を明らかにする上で、重要な知見を提供したことになる。