Exploring a way to increase the survival ratio of inoculated microorganisms in open soil system in corporation with mathmatical modelings

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K19220
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Research Field: Agricultural chemistry and related fields
• Research Institution: The University of Tokyo
• Principal Investigator: OTSUKA Shigeto 東京大学, 大学院農学生命科学研究科(農学部), 准教授 (10313074)
• Co-Investigator(Kenkyū-buntansha): 島田 尚 東京大学, 大学院工学系研究科(工学部), 准教授 (90431791)
• Project Period (FY): 2017-06-30 – 2020-03-31
• Keywords: 土壌微生物 / 開放系土壌 / 微生物群集構造 / 微生物群集機能 / 制御 / 数理的特性

Outline of Final Research Achievements

The original purpose of this study was to extend the survival time of a beneficial bacterium in an open soil system by inoculation with another "partner bacterium". But based on the results from network analyses, I changed the strategy and succeeded in increasing the proportion of particular soil bacteria in the community by amending low molecular organic matters into soil. By this, basic knowledge was obtained to control microbial community function with the robustness of the community structure being maintained based on the rank-size abundance. The relationship between an amended compound and the functional change is still under investigation, but so far I obtained a result that the amendment of a kind of plant root exudate compound into soil enhances the phosphorus circulation in soil driven by microorganisms.

Free Research Field

土壌微生物学

Academic Significance and Societal Importance of the Research Achievements

開放系土壌における微生物機能の制御は困難であり、有用な微生物を土壌に投入しても生残せず、また機能を十分に発揮しないと考えられている。本研究では、土壌に微生物を投入するのではなく、元々生息してる微生物の機能を制御できる可能性を見出した点で、応用的な意義が大きい。また、ありふれた低分子有機物の添加だけで土壌中の微生物群集構造やその群集機能を変化させられること、また、変化の仕方に数理的特異性が認められた点は、新たな研究分野の開拓につながる学術意義を有している。