Work

Arbuscular mycorrhizal inoculation enhances Robinia pseudoacacia performance in zinc-contaminated soils via improved nutrient use and stress mitigation

Year: 2025

Type: article

Abstract: Arbuscular mycorrhizal fungi (AMF) are recognized for their ability to mitigate the effects of zinc (Zn) stress in plants, though the underlying mechanisms are not fully understood. In this study, Robinia pseudoacacia seedlings were exposed to varying levels of Zn stress (0, 500, and 1000 mg · kg - 1 ) with or without inoculation of Rhizophagus irregularis to explore how AMF symbiosis affects Zn uptake, phosphorus (P) acquisition, abscisic acid (ABA) distribution, and photosynthetic performance. Compared with the control, 500 mg · kg -1 Zn reduced shoot and root biomass by 35% and 28%, respectively, whereas 1000 mg · kg -1 Zn caused stronger inhibition, with reductions of 60.8% and 56.0%. Root P decreased by 25% and 40%, ABA distribution was altered, and photosynthetic rate and PSII efficiency declined. AMF inoculation mitigated these effects: Zn accumulation in roots and shoots decreased by 35%, with higher root-to-shoot Zn ratios, which indicates enhanced Zn sequestration in roots. AMF-colonized plants also showed improved P uptake (40.4%-75.1%), increased ABA levels in roots (52.5%-169.6%), and alleviated reductions in biomass, net photosynthetic rate, and PSII efficiency under Zn stress. Additionally, the expression of photosynthesis-related genes ( RprbcS , RppsbA , and RppsbD ) was significantly upregulated in AMF-colonized plants. These findings suggest that AMF enhance tolerance to Zn stress in Robinia pseudoacacia by limiting Zn translocation to shoots, improving P acquisition, modulating ABA allocation, and maintaining photosynthetic efficiency. • Arbuscular mycorrhizal fungi mitigated zinc-induced growth inhibition and photosynthetic decline in Robinia pseudoacacia. • Arbuscular mycorrhizal symbiosis restricted zinc translocation from roots to shoots and improved zinc sequestration in roots. • Mycorrhizal plants exhibited enhanced phosphorus uptake and altered abscisic acid distribution under zinc stress. • Upregulation of RprbcS , RppsbA , and RppsbD genes helped maintain photosynthetic efficiency in mycorrhizal-treated plants. • The findings provide insight into arbuscular mycorrhizal-mediated zinc tolerance mechanisms via nutrient regulation and hormonal balance.

Source: Plant Physiology and Biochemistry

DOI: 10.1016/j.plaphy.2025.111008

Authors: Yu Zhang, Xiao Lou, Hui Chen, Tingying Xu, Ming Tang

Institutions: South China Agricultural University, Shanxi Medical University, Oklahoma State University

Language: English

Topic: Mycorrhizal Fungi and Plant Interactions

Subfield: Plant Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: hybrid

Estimated APC paid: $3,990