[Impacts of arbuscular mycorrhizal fungi (AMF)on growth, N bio-fixation, and phosphorus uptake of legume crop]

To explore the effects of arbuscular mycorrhizal fungi (AMF) on the growth of legume crop, pot and field experiments with soybean were conducted. Treatments of inoculation (+AMF) and non-inoculation with AMF (-AMF) were set up for the pot experiment, and AMF mycelium non-limited and limited for the field experiment. Results of the pot experiment showed that inoculation with AMF significantly increased soybean aboveground biomass (16.5%) and root nodules number (131.4%), above-ground plant phosphorus and nitrogen concentrations and uptakes. In the field trial, the above-ground and root biomasses and root nodules number under AMF mycelium non-limited were significantly increased by 123.6%, 61.5%, and 212.5% compared with those under the limited condition, respectively. Plant phosphorus uptake, nitrogen concentration and uptake, and soil available nitrogen and phosphorus concentrations were significantly higher under AMF mycelium non-limited than the limited both in both shoot and root. Our findings provide theoretical reference for further understanding the relationship between legume crop and AMF, as well as the efficient utilization of phosphorus fertilizer.