Advantages linked to root development enhance rice biomass accumulation under elevated carbon dioxide conditions

作者：Jiang He, Weiyang Zhang, Kuanyu Zhu, Zhiqin Wang, Weilu Wang, Jianchang Yang · 发表于：Agronomy Journal · 年份：2020 · DOI：10.1002/agj2.20357 · 被引用次数：2 · 研究领域：Plant responses to elevated CO2、Soil Carbon and Nitrogen Dynamics、Plant Stress Responses and Tolerance

Abstract To explore the effects of an increased CO 2 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 CO 2 (400 μmol mol −1 ) and elevated CO 2 (600 μmol mol −1 ) combined with high N (2.5 mM) and low N (0.5 mM) treatments. The effects of elevated CO 2 on root morphological and physiological characteristics, N uptake and utilization, and dry matter accumulation and distribution were analyzed. The results showed that the elevated CO 2 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 CO 2 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 CO 2 significantly increased the N accumulation of LY but decreased the N uptake of NJ under low N. Under elevated CO 2 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 CO 2 . Improvements in the root morphology and physiological activity of rice in future breeding efforts should enhance the dry matter production of low‐response rice.