Nitrogen transfer mechanism of mycorrhizal network between Pinus massoniana Lamb. seedlings

Abstract The common mycorrhizal network is to facilitate the underground interchange of materials and information between plants. What the common mycorrhizal network does for plants and the environment yet unknown. The mixed strains (Sm) of Pisolithus orientalis (Po), Scleroderma citrinum (Sc), Suillus luteus (Sl) and non-inoculation (CK) were taken. Varying nitrogen concentrations by used ¹⁵N isotope labeling to investigate the impact of mycorrhizal network of Pinus massoniana Lamb. The recipient seedlings could contract mycelia from the donor, the higher of infection rate, the greater of growth and ability to absorb nutrients. P. massoniana seedlings could benefit from both inoculation and nitrogen treatment for growth and nutrient uptake. Under the same nitrogen treatment, donor/recipient seedlings of Sm exhibited a greater uptake of nitrogen compared to those of CK. Under Sm treatment, the ¹⁵N absorption by donor/recipient seedlings was the highest at N6 and N4, the ¹⁵N utilization and transfer rates were the highest at N4, and the ¹⁵N allocation rates were highest in roots at N2 and N6, in leaves at N4 (45.21% and 50.59%, respectively). The ¹⁵N transfer rate had a major impact on the biomass of recipient seedlings, ¹⁵N absorption, and ¹⁵N allocation. Sm-N4 treatment performed well in these areas.