Nitrogen deficiency drives fungal compositional shifts without functional changes in wheat rhizosphere
02 March 2025 by smartfertiliser-hub
Lok Hang Chan, Shu Kee Lam, Deli Chen, Caixian Tang, Qinglin Chen, Ute Roessner, Hang-Wei Hu. “Nitrogen deficiency drives fungal compositional shifts without functional changes in wheat rhizosphere,” Rhizosphere. DOI: https://doi.org/10.1016/j.rhisph.2025.101030
Nitrogen (N) deficiency reduces crop yield, but this effect may be mitigated by symbiotic interactions between crops and fungi. However, the response of wheat-fungal interactions to N deficiency remains unclear. We hypothesised that wheat cultivars with a higher reported nitrogen use efficiency (NUE), would induce shifts in the fungal community composition and functional profiles within the wheat rhizosphere to tolerate N deficiency. A glasshouse experiment was conducted to examine the effects of N deficiency on the rhizosphere fungal communities of wheat (Triticum aestivum L.) cultivars Gladius (low N-use efficiency) and Mace (high N-use efficiency). Plants were grown until the mid-anthesis stage in a Dermosol soil treated with either 0 (Low-N) or 90 kg N ha⁻1 (High-N). The rhizosphere fungal communities were characterised using quantitative PCR, ITS rRNA metabarcoding, and metagenomics. The abundance and diversity of the rhizosphere fungal community were not significantly influenced by N deficiency in either Mace or Gladius cultivars (P > 0.05). However, the fungal community composition showed significant variation across N treatments in Mace (P < 0.05), whereas no such effect was observed in Gladius (P > 0.05). Differential abundance analysis and fungal trait predictions indicated a reduction in fungal symbionts in both cultivars under N deficiency (P < 0.05). Metagenomic analysis demonstrated that fungal functional profiles remained unaffected by N deficiency (P > 0.05) but significantly differed between Mace and Gladius (P < 0.05). This study reveals intraspecific variation in rhizosphere fungal responses to N deficiency between Mace and Gladius. The metabarcoding and metagenomic data suggest functional redundancy within the fungal community, which may enhance wheat resilience under N-deficient conditions. These findings highlight the potential of using fungal community stability in developing biofertiliser products for sustainable agriculture.
