Effects of belowground interactions on crop yields and nutrient uptake in maize-faba bean relay intercropping systems

Belowground interactions are crucial in the over-yielding of intercropping systems. However, the effects of belowground interactions on the yields of intercrops in faba bean-maize relay intercropping system are still unclear. In this study, field and pot experiments were conducted, and the biomass, yield, nutrient accumulation and photosynthetic parameters of intercrops were determined to analyze the effects of belowground interactions and relay intercropping. In the field experiments, the yield and biomass of faba bean and maize in the relay intercropping system was significantly increased compared with the monocropping. The relay intercropping promoted the accumulation of nitrogen and phosphorus in faba bean and maize but showed no effect on potassium accumulation. In the pot experiments, no barrier treatment significantly increased the nutrient accumulation of faba bean and maize, nutrient content in soil, photosynthesis, maize, yield, biomass, plant height, 100-grain weight of faba bean and maize. In summary, relay intercropping increased nutrient accumulation, photosynthesis, biomass and yield of crops. The belowground interactions of intercrops could provide good soil fertility conditions for crop growth. The results can provide references for high-yield cultivation of crops and sustainable development of agriculture.