2019 Fiscal Year Final Research Report
Isotope phenomics: the quest for ideal phenotypes of rice plants under elevated-CO2 world
Project/Area Number |
16H06204
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Research Category |
Grant-in-Aid for Young Scientists (A)
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Allocation Type | Single-year Grants |
Research Field |
Agricultural environmental engineering/Agricultural information engineering
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Research Institution | National Agriculture and Food Research Organization |
Principal Investigator |
Tokida Takeshi 国立研究開発法人農業・食品産業技術総合研究機構, 農業環境変動研究センター, 主任研究員 (20585856)
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Project Period (FY) |
2016-04-01 – 2019-03-31
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Keywords | 水田 / 高CO2 / イネ / メタン |
Outline of Final Research Achievements |
Rice paddies provide staple food for half the world population while they represent one of the largest anthropogenic sources of atmospheric CH4, a potent greenhouse gas. In this study, free-air CO2 enrichment (FACE) experiment was conducted to study responses of rice plants and CH4 emissions to elevated [CO2], and we found rice cultivars/lines that exhibited higher e-[CO2] responsiveness than that of a popular Japanese cultivar (cv. Koshihikari). Large sink capacity was identified as one of the most important traits for the responsiveness. We also found low CH4-emitting cultivars/lines but possess good e-[CO2] responsiveness in grain yield. Isotopic analyses showed that lower CH4 production from soil organic matter (SOM) and/or greater oxidation of SOM-born CH4, presumably being relevant to greater root development, were the major mechanisms responsible for the lower CH4-emission genotypes.
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Free Research Field |
農業環境工学
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Academic Significance and Societal Importance of the Research Achievements |
増え続ける世界人口を養いつつ地球温暖化問題を解決するため、高CO2に対するコメ収量の応答を高めつつ、温室効果ガスであるメタンの排出を抑制する水田稲作が必要とされている。本研究で見出された高CO2に対する応答性の高い品種やその形質は、増加し続ける大気CO2を増収に結びつけるイネを選抜・育成する上で重要な知見である。また水田からのメタン排出については、これまで生産面とのトレードオフや、高CO2による排出増加の可能性が強調されてきた。本研究の結果、多収かつ高CO2応答が大きくてもメタン排出量が少ない品種が見出され、高CO2時代にコメ生産の増加とメタン排出低減を両立する新たな道筋が拓けた。
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