Leaf senescence as a natural 'free radical factory' producing environmentally persistent free radicals

Hongke Feng; Xingzhi Jin; Fuxuan Ren; Peilin Yang; Junjie Wang; Xiaohu Zhang; Yi Yang; Jianwei Li; Hao Chen; Peng Cai; Xing Ding

doi:10.59717/j.xinn-geo.2026.100241

The Innovation Geoscience > 2026 Vol. 4 > No. 3 > 100241

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Leaf senescence as a natural "free radical factory" producing environmentally persistent free radicals

1.
College of Chemistry, Huazhong Agricultural University, Wuhan 430070, China
2.
National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
3.
Hubei Key Laboratory of Soil Environment and Pollution Remediation, Huazhong Agricultural University, Wuhan 430070, China
4.
Macao Institute of Materials Science and Engineering (MIMSE), Faculty of Innovation Engineering, Macau University of Science and Technology, Macao SAR 999078, China

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Corresponding authors: dingx@mail.hzau.edu.cn (X.D.); cp@mail.hzau.edu.cn (P.C.)
Received Date: December 17, 2025

Accepted Date: June 09, 2026

Published Online: June 10, 2026

The Innovation Geoscience 4(3), https://doi.org/10.59717/j.xinn-geo.2026.100241 | Cite this article

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PUBLIC SUMMARY
1. Leaf senescence produces environmentally persistent free radicals (EPFRs), a newly identified natural source.
  
  Cell wall remodeling and lignin accumulation provide phenolic sites for stabilizing EPFRs during senescence.
  
  Declining antioxidants and elevated oxidative stress drive EPFRs formation in senescent leaves.
  
  Senesced crop residues contain high levels of EPFRs, potentially impacting soil health and carbon cycling.
  
  The senescence program itself, not merely water loss, is the key driver of EPFRs generation.

ABSTRACT

ABSTRACT

Environmentally persistent free radicals (EPFRs) are emerging pollutants of global concern, yet their natural sources remain largely undefined. Here, we identify natural leaf senescence as a major, previously unrecognized source of EPFRs in terrestrial ecosystems. By conducting a cross-species analysis of woody and herbaceous plants, we show that EPFR formation is consistently triggered during senescence, producing markedly elevated electron paramagnetic resonance (EPR) signals compared with mature foliage. Importantly, this radical generation is driven by the senescence process itself—rather than mere water loss. Mechanistic analyses reveal that cell wall remodeling, characterized by lignin accumulation, provides phenolic-rich reaction sites for radical stabilization, while concurrent antioxidant depletion and heightened oxidative stress create a permissive redox environment. Our findings establish plant senescence as a critical biological generator of EPFRs, with implications for understanding radical fluxes in the soil–plant–atmosphere continuum and for re-evaluating the environmental impact of agricultural residue management.
- Environmentally /
- persistent /
- free /
- radicals /
- (EPFRs)/Leaf /
- senescence/Lignin /
- accumulation/Cell /
- wall /
- remodeling/Oxidative /
- stress

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Feng H., Jin X., Ren F., et al. (2026). Leaf senescence as a natural 'free radical factory' producing environmentally persistent free radicals. The Innovation Geoscience 4:100241. https://doi.org/10.59717/j.xinn-geo.2026.100241

Feng H., Jin X., Ren F., et al. (2026). Leaf senescence as a natural "free radical factory" producing environmentally persistent free radicals. The Innovation Geoscience 4:100241. https://doi.org/10.59717/j.xinn-geo.2026.100241

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Leaf senescence as a natural "free radical factory" producing environmentally persistent free radicals

GRAPHICAL ABSTRACT

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