Trichoderma Priming Boosts Free-Living Nitrogen Cyclers and Stress Resilience in Chickpea

A new study published in Plant & Soil reveals that priming chickpea seeds with the beneficial fungus Trichoderma asperellum T42 can dramatically reshape the rhizosphere microbiome—shifting nitrogen acquisition from traditional root nodulation toward free-living nitrogen cyclers, even under severe salinity or Fusarium wilt stress.

Trichoderma Priming Alters Root Microbiome Dynamics

Researchers treated chickpea cultivar JG-315 seeds with T. asperellum T42 and exposed plants to Fusarium wilt (Fusarium oxysporum f. sp. ciceris) and high salinity. They then tracked root-associated bacterial diversity, nitrogen uptake, and gene expression patterns across two plant generations.

The findings showed strong microbiome restructuring.
T42-treated plants under stress exhibited:

Increased populations of halo-tolerant bacteria under salinity
More plant-growth promoting and pathogen-antagonistic species under Fusarium stress
Lower abundance of chickpea-associated rhizobia
Higher abundance of free-living nitrogen-fixing genera such as Nitrososphaera, Nostoc, and Nitrospira

This shift indicates that Trichoderma can act as a situation-specific microbiome modulator, helping the plant recruit stress-relevant microbial partners more efficiently.

Reduced Nodulation but Enhanced Nitrogen Uptake

Despite fewer nodules in T42-treated plants, overall nitrogen uptake did not decrease. Instead, the study reported:

Upregulation of nitrate transporter genes
Downregulation of nodulation genes
Stable or improved plant nitrogen levels under stress

This suggests chickpea plants compensated for reduced symbiotic nitrogen fixation by relying more on nitrate supplied by free-living nitrogen fixers enriched in the rhizosphere.
Chickpea priming with Trichoder…

Effects Persist Into the Next Generation

F1 generation chickpea plants grown from T42-treated seeds maintained the same nitrogen-acquisition strategy. The enhanced expression of nitrate transporters persisted, hinting at a possible epigenetic memory of microbial priming.

A New Direction in Sustainable Nitrogen Management

The work shows that Trichoderma asperellum T42 can:

Rebalance rhizosphere communities under biotic and abiotic stress
Promote free-living nitrogen cycling
Boost nitrogen uptake efficiency
Reduce dependence on rhizobial nodulation

For chickpea production in stress-prone soils, this represents a powerful biological strategy for improving plant resilience and minimizing fertilizer inputs.

Reference

Rashid, M.M., Aditya, K., Singh, D.P. et al. Chickpea priming with Trichoderma asperellum T42 enriches free-living nitrogen cyclers in rhizosphere and enhances nitrogen uptake in off-springs under stress. Plant Soil (2025). https://doi.org/10.1007/s11104-025-08095-x