Arbuscular Mycorrhization Enhances Nitrogen, Phosphorus and Potassium Accumulation in <i>Vicia faba</i> by Modulating Soil Nutrient Balance under Elevated CO₂

• Main Authors: Songmei Shi, Xie Luo, Xingshui Dong, Yuling Qiu, Chenyang Xu, Xinhua He
• Format: Article
• Language: English
• Published: MDPI AG 2021-05-01
• Series: Journal of Fungi
• Subjects: AMF; biomass production; carbon dioxide enrichment; nutrient absorption; soil nitrogen content; soil organic carbon
• Online Access: https://www.mdpi.com/2309-608X/7/5/361

Effects of arbuscular mycorrhizal fungi (AMF), elevated carbon dioxide (eCO₂), and their interaction on nutrient accumulation of leguminous plants and soil fertility is unknown. Plant growth, concentrations of tissue nitrogen (N), phosphorus (P), and potassium (K) in 12-week-old nodulated faba bean (<i>Vicia faba</i>, inoculated with <i>Rhizobium leguminosarum</i> bv. NM353), and nutrient use efficiency were thus assessed under ambient CO₂ (410/460 ppm, daytime, 07:00 a.m.–19:00 p.m./nighttime, 19:00 p.m.–07:00 a.m.) and eCO₂ (550/610 ppm) for 12 weeks with or without AM fungus of <i>Funneliformis mosseae</i> inoculation. eCO₂ favored AMF root colonization and nodule biomass production. eCO₂ significantly decreased shoot N, P and K concentrations, but generally increased tissue N, P and K accumulation and their use efficiency with an increased biomass production. Meanwhile, eCO₂ enhanced C allocation into soil but showed no effects on soil available N, P, and K, while AM symbiosis increased accumulation of C, N, P, and K in both plant and soil though increased soil nutrient uptake under eCO₂. Moreover, plant acquisition of soil NO₃⁻–N and NH₄⁺–N respond differently to AMF and eCO₂ treatments. As a result, the interaction between AM symbiosis and eCO₂ did improve plant C accumulation and soil N, P, and K uptake, and an alternative fertilization for legume plantation should be therefore taken under upcoming atmosphere CO₂ rising. Future eCO₂ studies should employ multiple AMF species, with other beneficial fungal or bacterial species, to test their interactive effects on plant performance and soil nutrient availability in the field, under other global change events including warming and drought.