Interactive effects of elevated CO2 concentration and nitrogen form on dry matter production and nitrogen accumulation of some crop species

Research Project

Project/Area Number	24780018
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Multi-year Fund
Research Field	Crop science/Weed science
Research Institution	National Agriculture and Food Research Organization
Principal Investigator	KUMAGAI Etsushi 独立行政法人農業・食品産業技術総合研究機構, 東北農業研究センター生産環境研究領域, 研究員 (80583442)
Project Period (FY)	2012-04-01 – 2015-03-31
Project Status	Completed (Fiscal Year 2014)
Budget Amount *help	¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000) Fiscal Year 2014: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000) Fiscal Year 2013: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000) Fiscal Year 2012: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
Keywords	乾物生産 / 光合成 / 硝酸還元 / 窒素吸収 / 高CO2濃度 / 無機窒素形態 / 吸水 / 亜硝酸還元 / アンモニア同化 / 硝酸 / アンモニア / 窒素同化
Outline of Final Research Achievements	Aiming to establish the adaptive nitrogen (N) management to future high CO2 environment, I investigated whether the responsiveness of biomass production and N concentration to CO2 enrichment varied among crop species differing in preference to nitrogen forms (nitrate vs ammonium). Rice plants (preference to ammonium) received ammonium nutrition showed the greater biomass enhancement to CO2 enrichment than ones received nitrate nutrition. In both pea and spinach (preference to nitrate), opposite results were obtained: Plants received nitrate nutrition showed the greater biomass enhancement. In spinach, the decline of N concentration due to elevated CO2 was observed in plants received nitrate, but not in plants received ammonium. This phenomenon resulted from the inhibition of nitrate assimilation in leaves rather than nitrate absorption in roots.