Mulberry-soybean intercropping reshapes rhizosphere metabolites and microbiota alongside enhanced soybean nodulation.

Mulberry-soybean intercropping with full root contact increases soybean nodulation and nitrogen fixation by over 20% compared to monoculture systems.

• Why it matters: Understanding belowground interactions in intercropping systems is crucial for improving nitrogen-use efficiency and sustainable crop production, yet these links remain poorly understood.
• What they did: A greenhouse experiment compared monocultures and two intercropping setups, assessing plant traits, rhizosphere metabolites, and microbial communities across six replicates, with detailed metabolomics and microbiome profiling.
• The result: Full-root contact intercropping significantly enhanced soybean nodulation, nitrogenase activity, and plant nitrogen accumulation, with distinct rhizosphere metabolite and microbiota shifts, especially under continuous root contact.