Screening and application of microbes adhering to the roots of Lemnoideae with stable affinity

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K12217
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 64020:Environmental load reduction and remediation-related
• Research Institution: University of Yamanashi
• Principal Investigator: Tanaka Yasuhiro 山梨大学, 大学院総合研究部, 准教授 (50377587)
• Co-Investigator(Kenkyū-buntansha): 遠山 忠 山梨大学, 大学院総合研究部, 教授 (60431392) ; 森 一博 山梨大学, 大学院総合研究部, 教授 (90294040)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: ウキクサ / メタノール資化性細菌 / 植物生育促進細菌

Outline of Final Research Achievements

This study aimed to identify microbes with a high affinity for the roots of duckweed, which could be used to develop a new phytoremediation system for water purification. By comparing the microbial communities formed on the roots of 14 duckweed samples, the target microbes were identified. As a result, Comamonadaceae etc. were identified as the candidate at the family level. At the genus level, Methylophilus etc. were markedly dominant on the roots of duckweed, indicating that these microbes closely interact with duckweed with high affinity. Five strains of Methylophilaceae showing plant growth-promoting activity for duckweed were successfully obtained. Additionally, we introduced a phenol-degrading bacterial strain within the family Comamonadaceae to the roots of duckweed. The resultant functionally enhanced duckweed showed stable phenol-degrading activity after exposure to environmental water containing various types of indigenous microbes.

Free Research Field

環境微生物学

Academic Significance and Societal Importance of the Research Achievements

Methylophilus属をはじめとしたメタノール資化性細菌がウキクサ亜科植物の根と親和性が高いことを明らかにした。また、Methylophilus属としては初めてウキクサの生育を促進する菌株（PGPB）を得た。
ウキクサ亜科植物を利用した高効率なバイオマス生産、新しい汚水処理技術の開発につながる知見を得た。