Zhu Xiancan, Song Fengbin, Liu Shengqun, Liu Fulai
Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, People's Republic of China.
Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Taastrup, DK-2630, Denmark.
Mycorrhiza. 2016 Feb;26(2):133-40. doi: 10.1007/s00572-015-0654-3. Epub 2015 Jul 7.
Effects of the arbuscular mycorrhizal (AM) fungus Rhizophagus irregularis on plant growth, carbon (C) and nitrogen (N) accumulation, and partitioning was investigated in Triticum aestivum L. plants grown under elevated CO2 in a pot experiment. Wheat plants inoculated or not inoculated with the AM fungus were grown in two glasshouse cells with different CO2 concentrations (400 and 700 ppm) for 10 weeks. A (15)N isotope labeling technique was used to trace plant N uptake. Results showed that elevated CO2 increased AM fungal colonization. Under CO2 elevation, AM plants had higher C concentration and higher plant biomass than the non-AM plants. CO2 elevation did not affect C and N partitioning in plant organs, while AM symbiosis increased C and N allocation into the roots. In addition, plant C and N accumulation, (15)N recovery rate, and N use efficiency (NUE) were significantly higher in AM plants than in non-AM controls under CO2 enrichment. It is concluded that AM symbiosis favors C and N partitioning in roots, increases C accumulation and N uptake, and leads to greater NUE in wheat plants grown at elevated CO2.
通过盆栽试验，研究了丛枝菌根（AM）真菌不规则球囊霉对在高浓度二氧化碳环境下生长的普通小麦植株生长、碳（C）和氮（N）积累及分配的影响。将接种或未接种AM真菌的小麦植株种植在两个二氧化碳浓度不同（400和700 ppm）的温室隔间中，为期10周。采用¹⁵N同位素标记技术追踪植株对氮的吸收。结果表明，高浓度二氧化碳增加了AM真菌的定殖。在二氧化碳浓度升高的情况下，AM植株比非AM植株具有更高的碳浓度和更高的植株生物量。二氧化碳浓度升高不影响植物器官中碳和氮的分配，而AM共生增加了碳和氮向根部的分配。此外，在二氧化碳浓度升高的情况下，AM植株的碳和氮积累、¹⁵N回收率以及氮利用效率（NUE）均显著高于非AM对照。得出的结论是，AM共生有利于根部碳和氮的分配，增加碳积累和氮吸收，并使在高浓度二氧化碳环境下生长的小麦植株具有更高的氮利用效率。
