Effects of alfalfa intercropping on soil carbon, nitrogen, and phosphorus and the fungal community in the rhizosphere of soils in silage maize

Under the control of monoculture silage maize (Zea mays) and the intercropped alfalfa (Medicago sativa) model, we measured the index of soil C, N, P, microbial biomass C (MBC), microbial biomass N (MBN), microbial biomass P (MBP), glomalin-related soil proteins (GRSP), soil fungal diversity, and community structure characteristics in the soil rhizosphere of early-maturing and late-maturing maize. The results illustrated that the total N content in the soil rhizosphere of the two types of maize increased significantly (P < 0.05) in the first year, indicating that intercropping may enhance the activity of soil N fixing microoganism. The intercropping significantly increased the content of MBN, MBP, late-maturing soil MBC, and easily extractable glomalin (EEG) in the soil rhizosphere of early maturing maize (P < 0.05), and the characteristics of the rhizosphere soil fungal communities tended to be similar. This indicated that intercropping may improve soil nutrient supply and promote soil microbial activities, thereby improving soil fertility and promoting plant growth. Therefore, according to the analysis of results of soil physical and chemical properties and fungi in the first year, the alfalfa and silage maize intercropping in the Guanzhong area may effectively improve the efficiency of soil nutrient element utilization.