Effects of Nitrate and Ammonium Nitrogen on AM Colonization and Nitrogen and Phosphorus Uptake in Triticum aestivum and Vicia faba Intercropping System

Exploring the effects of different forms of nitrogen application on nitrogen and phosphorus uptake and mycorrhizal formation in the intercropping system of Triticum aestivum and Vicia faba. Through the pot experiment, nitrate nitrogen(Ca(NO₃)₂) and ammonium nitrogen((NH₄)₂SO₄) were used to determine the shoots and roots plant biomass, nitrogen and phosphorus uptake, mycorrhizal infection rate and rhizosphere soil mycelium density. The findings indicated that application of nitrate nitrogen promoted the shoots and roots biomass of intercropped T. aestivum, but the opposite of V. faba. Nitrate nitrogen treatment increased the nitrogen and phosphorus absorption of intercropping T. aestivum shoots and roots by 73.17%, 76.27% and 123.79%, 65.51%; the nitrogen and phosphorus uptake of shoots and roots parts of intercropping T. aestivum and V. faba under ammonium nitrogen showed opposite trends. Nitrate nitrogen treaments reduced the mycorrhizal infection rates of intercropping T. aestivum and V. faba by 22.71% and 60.72%; under ammonium nitrogen, the mycorrhizal infection rate and soil mycelial density of intercropping T. aestivum increased by 40.05% and 45.24%, and the mycorrhizal infection rate of V. faba increased by 17.63%. During the jointing of T. aestivum and the flowering period of V. faba, nitrate nitrogen application promoted the biomass, nitrogen and phosphorus uptake of intercropping wheat, and reduce the mycorrhizal infection rate of intercropping T. aestivum and V. faba.