Work

Pre-acclimation to low nitrogen enhances drought tolerance in Lolium perenne through integrated metabolic and transcriptional alterations

Year: 2026

Type: article

Abstract: Drought stress is a major constraint on the productivity of temperate forage grasses such as perennial ryegrass ( Lolium perenne ). While nitrogen management is widely employed in agronomic practice, its specific role in mediating drought adaptation strategies remains unclear. This study aimed to systematically characterize the response of perennial ryegrass to drought stress following low nitrogen pre-acclimation through integrated physiological and transcriptomic analyses during both stress and recovery phases. Our results demonstrated that drought severely impaired photosynthetic capacity and induced oxidative damage in non-acclimated plants, as evidenced by the significant reductions in net photosynthetic rate, stomatal conductance and PSII efficiency ( Fv / Fm ), alongside elevated malondialdehyde (MDA) levels and increased activities of key antioxidant enzymes (e.g., ascorbate peroxidase, peroxidase and catalase). In contrast, low nitrogen pre-acclimation effectively preserved photosynthetic performance under subsequent drought, mitigating declines in gas exchange parameters and maintaining PSII integrity. These pre-acclimated plants also exhibited reduced oxidative stress under drought and superior recovery capacity after rewatering. This enhanced drought tolerance was associated with fructan accumulation and tempered transcriptional responses. Low nitrogen pre-acclimation mitigated the drought-induced transcriptional upheaval, attenuated the activation of hormonal signaling pathways and MAPK cascades, significantly alleviated the downregulation of genes encoding photosynthetic apparatus, stabilized chlorophyll metabolism and optimized carbon-nitrogen balance. These findings reveal a nitrogen-mediated priming mechanism that enhances drought tolerance through integrated metabolic and transcriptional adjustments, providing new insights into the interaction between nutrient signaling and stress resistance, as well as potential strategies for enhancing plant tolerance under climate change. • Low nitrogen pre-acclimation primes drought tolerance in Lolium perenne. • Pre-acclimation mitigates photosynthetic decline and oxidative damage under drought. • Maximized fructan accumulation and optimized C/N balance underpin tolerance. • A unique transcriptional reprogramming drives the primed, coordinated response. • Reveals a nitrogen mediated cross-stress memory mechanism for enhanced tolerance.

Source: Plant Physiology and Biochemistry

DOI: 10.1016/j.plaphy.2026.111109

Authors: Hui Zuo, Xinyue Xiong, Yuqian Chen, Qianqian Guo

Institution: Beijing Forestry University

Language: English

Topic: Plant Stress Responses and Tolerance

Subfield: Plant Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: hybrid

Estimated APC paid: $3,990