To explore the effects of an increased CO₂ concentration on the growth and N absorption and utilization of different rice (Oryza sativa L.) cultivars, the Liangyoupeijiu (LY) and Nanjing 9108 (NJ) rice cultivars were grown under ambient CO₂ (400 μmol mol⁻¹) and elevated CO₂ (600 μmol mol⁻¹) combined with high N (2.5 mM) and low N (0.5 mM) treatments. The effects of elevated CO₂ on root morphological and physiological characteristics, N uptake and utilization, and dry matter accumulation and distribution were analyzed. The results showed that the elevated CO₂ levels significantly increased the total biomass of LY under different N levels but only significantly increased the total biomass of NJ under high N. Elevated CO₂ significantly increased the N concentrations in the organs of LY but had no significant effect on the N concentrations in the organs of NJ. As a result, elevated CO₂ significantly increased the N accumulation of LY but decreased the N uptake of NJ under low N. Under elevated CO₂ conditions, the total root length and root surface area of LY increased, and the roots also maintained high activity. The larger roots and higher physiological activity and N accumulation of LY were the important reasons for the high levels of dry matter production in response to elevated CO₂. Improvements in the root morphology and physiological activity of rice in future breeding efforts should enhance the dry matter production of low‐response rice.

中文翻译：

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与根系发育相关的优势提高了二氧化碳条件下水稻生物量的积累

为了研究增加的CO ₂浓度对不同水稻（Oryza sativa L.）品种的生长以及氮吸收和利用的影响，在环境CO ₂（400 ）下种植了两优培九（LY）和南京9108（NJ）水稻。μmolmol ^-1）和升高的CO ₂（600μmolmol ^-1）结合高N（2.5 mM）和低N（0.5 mM）处理。分析了CO ₂浓度升高对根系形态和生理特性，氮素吸收利用及干物质积累与分配的影响。结果表明，升高的CO ₂水平在不同氮水平下显着增加了LY的总生物量，但在高氮水平下仅显着增加了NJ的总生物量。升高的CO ₂显着增加了LY器官中的N浓度，但对器官中的N浓度没有显着影响新泽西州 结果，升高的CO ₂显着增加了低氮条件下LY的氮积累，但降低了NJ的氮吸收。在升高的CO ₂条件下，LY的总根长和根表面积增加，并且根也保持高活性。较大的根，较高的生理活性和LY的氮积累是响应CO ₂升高而产生高水平干物质的重要原因。。在未来的育种工作中，水稻根系形态和生理活性的改善应提高低响应水稻的干物质生产。