Work

Ectomycorrhizal-mediated lignin pathway activation enhances phosphorus use efficiency in Pinus massoniana

Year: 2025

Type: article

Abstract: Phosphorus (P) is a key limiting nutrient for plant growth and productivity in forest ecosystems. Ectomycorrhizal (ECM) fungi are known to enhance host P uptake and stress resilience, the metabolic regulatory mechanisms underlying this symbiosis remain unclear in coniferous species. In this study, we investigated the role of Scleroderma citrinum colonization in modulating low-P tolerance and phenylpropanoid metabolism in Pinus massoniana . Physiological analyses revealed that under prolonged low-P conditions, ECM-inoculated seedlings exhibited significantly improved growth, root development, and organ-level P accumulation compared to non-inoculated controls, indicating effective mitigation of P deficiency. Transcriptomic profiling demonstrated that ECM symbiosis systemically activated key branches of the phenylpropanoid pathway: in needles, PmCAD1 , PmCAD2 , and PmPRX1 were upregulated to promote monolignol biosynthesis and polymerization; in roots, PmPRX2 , as well as several 4CL , BGL , and REF family genes, were co-induced, contributing to cell wall remodeling and signal interface optimization. To further validate these transcriptomic insights, we functionally characterized two key genes, PmCAD3 and PmPRX7 , confirming their roles in lignin biosynthesis. After 20 days of P-deficient treatment, transgenic lines displayed no marked phenotypic differences but accumulated significantly higher shoot P content than wild-type plants, confirming their role in enhancing P acquisition and tolerance. Collectively, our findings supports the conclusion that ECM symbiosis is likely to improve the structural and metabolic adaptability of P. massoniana to low-phosphorus environments by activating phenylpropanoid-lignin biosynthetic module. This study provides new molecular insights into ECM-regulated nutrient adaptation in conifers and offers a theoretical basis for breeding low-P-efficient forestry species.

Source: Industrial Crops and Products

DOI: 10.1016/j.indcrop.2025.121828

Authors: Liangliang Li, Houying Chen, Guijie Ding

Institution: Guizhou University

Language: English

Topic: Mycorrhizal Fungi and Plant Interactions

Subfield: Plant Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

Open Access status: gold

Estimated APC paid: $3,720

Funders: National Natural Science Foundation of China, Natural Science Foundation of Guizhou Province, Science and Technology Program of Guizhou Province