Work

Legume–grass mixtures with arbuscular mycorrhizal fungi improve plant physiology, optimizing carbon and nitrogen dynamics and forage quality in perennial living mulches

Year: 2026

Type: article

Abstract: Introduction Perennial cover crops (also referred to as living mulches) represent an innovative management strategy that provides continuous soil cover throughout the year and supports organic production systems, agroforestry practices, and the adoption of sustainable agricultural systems. Although the benefits of annual cover crops are well documented, the potential benefit of perennial cover crops to enhance ecosystem services, including the potential for providing high-quality forage, remains underexplored. Methods To better understand the potential benefits of perennial cover crop mixtures, we quantified changes in plant physiology, biomass, and measures of forage quality across single- and mixed-species of clover ( Trifolium ambiguum ) and Kentucky bluegrass ( Poa pratensis ). We applied varying ratios of clover and grass (C 100 , C 75 -G 25 , C 50 -G 50 , C 25 -G 75 , G 100 ), with and without arbuscular mycorrhizal fungi (AMF) inoculation. Results Clover dominant mixtures, particularly C 75 –G 25 , exhibited higher leaf chlorophyll content and produced the greatest shoot biomass. This mixture, when inoculated with AMF, also showed the highest shoot C and N concentrations, with AMF increasing shoot and root C by 7–9% and N by 20–33%. Across monocultures and mixtures, AMF inoculation increased photosynthetic rates by 7.2% and reduced intercellular CO 2 concentrations by 4.1%, which was associated with greater C and N concentration. AMF inoculation also enhanced root network depth, width, surface area, and volume by 3.5–28.1% across all treatments. Forage quality was specific to the species, with clover providing higher protein, fat, and calcium contents, and grass providing greater dry matter, phosphorus, potassium, lignin, ADF, NDF, and dNDF 48 . Discussion Overall, our results demonstrate that mixed legume–grass systems, particularly when combined with AMF, optimized biomass production, C and N concentration, and forage quality.

Source: Frontiers in Plant Science

DOI: 10.3389/fpls.2026.1853351

Authors: Neda Nikpour Rashidabad, Ashley D. Keiser, Masoud Hashemi

Institution: University of Massachusetts Amherst

Language: English

Topic: Mycorrhizal Fungi and Plant Interactions

Subfield: Plant Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDGs: Zero hunger, Life on land

Open Access status: gold

Estimated APC paid: $3,801