Rice-straw extract directly stimulates pre-symbiotic arbuscular mycorrhizal fungal growth and is associated with greater phosphorus acquisition in Sorghum
- 1School of Life Sciences, Heilongjiang University
- 2School of Chemistry and Molecular Engineering, Shanghai Key Laboratory for Urban Ecological Processes and Eco-Restoration, East China Normal University
Abstract
Background: Improving arbuscular mycorrhizal fungal establishment may strengthen crop phosphorus acquisition and reduce dependence on phosphorus fertilizers. However, efficient symbiosis depends on fungal activation before root colonization, and practical approaches for stimulating this early stage remain limited.
Methods: We tested whether aqueous rice-straw extract (RSE) directly activates AMF and improves subsequent symbiosis with sorghum. Spore germination, hyphal growth, root colonization, recoverable extraradical spore density, plant biomass, phosphorus acquisition, and symbiosis-related gene expression were quantified. Phenolic-depleted RSE was included to assess the contribution of phenolic compounds.
Results: RSE showed a pronounced dose-dependent biphasic effect: low-to-moderate concentrations promoted AMF development, peaking at 0.3% with 74.1% spore germination, 18.48 mm hyphal length, and 27.5 branch points per spore, whereas 1.0% RSE markedly suppressed these responses. After 42 days, RSE increased root colonization from 22.5% to 51.3%, spore abundance from 58.4 to 106.4 per 50 g substrate, and extraradical hyphal length from 1.05 to 2.54 m per g. Shoot phosphorus uptake rose from about 2.3 to 5.9 mg per plant. Removing most phenolics markedly weakened these responses.
Conclusion: RSE directly stimulated pre-symbiotic AMF development and was associated with greater subsequent colonization and phosphorus acquisition. Reduced activity after partial phenolic depletion suggests that phenolics contributed to the response, although other water-soluble components may also be involved.
Related
- Soil Phosphorus Conditions Drives Arbuscular Mycorrhizal Fungal Community Differentiation and Modulate the Growth of Cenchrus pauciflorus
- Beyond phosphate uptake: PT4/PT11 as key functional components linking phosphate acquisition, nutrient exchange, and arbuscule maintenance in arbuscular mycorrhizal symbiosis
- Environmental variables associated with Arbuscular Mycorrhizal Fungi diversity in Ohio soybean agricultural systems.
- Arbuscular mycorrhizal fungi and mycorrhizal helper bacteria co-inoculation alters drought-associated physiological traits and leaf abscisic acid concentration in citrus rootstocks
- Machine Learning Identification of Functional Trait Syndromes Associated with Responsiveness to Arbuscular Mycorrhizal Fungi
BibTeX
@article{li2026ricestraw,
title = {{Rice-straw extract directly stimulates pre-symbiotic arbuscular mycorrhizal fungal growth and is associated with greater phosphorus acquisition in Sorghum}},
author = {Ruiqian Li and Qiankun Zeng},
journal = {Frontiers in Plant Science},
year = {2026},
month = oct,
doi = {10.3389/fpls.2026.1991797},
url = {https://www.frontiersin.org/articles/10.3389/fpls.2026.1991797/full},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Rice-straw extract directly stimulates pre-symbiotic arbuscular mycorrhizal fungal growth and is associated with greater phosphorus acquisition in Sorghum
AU - Ruiqian Li
AU - Qiankun Zeng
PY - 2026
DA - 2026/10/05
JO - Frontiers in Plant Science
DO - 10.3389/fpls.2026.1991797
UR - https://www.frontiersin.org/articles/10.3389/fpls.2026.1991797/full
AB - Background: Improving arbuscular mycorrhizal fungal establishment may strengthen crop phosphorus acquisition and reduce dependence on phosphorus fertilizers. However, efficient symbiosis depends on fungal activation before root colonization, and practical approaches for stimulating this early stage remain limited. Methods: We tested whether aqueous rice-straw extract (RSE) directly activates AMF and improves subsequent symbiosis with sorghum. Spore germination, hyphal growth, root colonization, recoverable extraradical spore density, plant biomass, phosphorus acquisition, and symbiosis-related gene expression were quantified. Phenolic-depleted RSE was included to assess the contribution of phenolic compounds. Results: RSE showed a pronounced dose-dependent biphasic effect: low-to-moderate concentrations promoted AMF development, peaking at 0.3% with 74.1% spore germination, 18.48 mm hyphal length, and 27.5 branch points per spore, whereas 1.0% RSE markedly suppressed these responses. After 42 days, RSE increased root colonization from 22.5% to 51.3%, spore abundance from 58.4 to 106.4 per 50 g substrate, and extraradical hyphal length from 1.05 to 2.54 m per g. Shoot phosphorus uptake rose from about 2.3 to 5.9 mg per plant. Removing most phenolics markedly weakened these responses. Conclusion: RSE directly stimulated pre-symbiotic AMF development and was associated with greater subsequent colonization and phosphorus acquisition. Reduced activity after partial phenolic depletion suggests that phenolics contributed to the response, although other water-soluble components may also be involved.
SN - 1664-462X
ER -