Green-synthesized lignin nanoparticles enhance Zea mays resilience to salt stress by improving antioxidant metabolism and mitigating ultrastructural damage

Muhammad Haseeb Javaid; Nana Chen; Muhammad Umair Yasin; Xingming Fan; Asifa Neelam; Muhammad Rehman; Zulqarnain Haider; Syed Asad Hussain Bukhari; Raheel Munir; Irshan Ahmad; Yinbo Gan

doi:10.1016/j.chemosphere.2024.142337

Green-synthesized lignin nanoparticles enhance Zea mays resilience to salt stress by improving antioxidant metabolism and mitigating ultrastructural damage

Chemosphere. 2024 Jul:359:142337. doi: 10.1016/j.chemosphere.2024.142337. Epub 2024 May 14.

Affiliations

¹ Zhejiang Key Laboratory of Crop Germplasm, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China.
² Institute of Food Crops, Yunnan Academy of Agricultural Sciences, Kunming, Yunnan, China.
³ Department of Agronomy, Faculty of Agriculture Sciences and Technology, Bahauddin Zakariya University, Multan, 60800, Pakistan.
⁴ Zhejiang Key Laboratory of Crop Germplasm, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China. Electronic address: ygan@zju.edu.cn.

PMID: 38754490
DOI: 10.1016/j.chemosphere.2024.142337

Abstract

Soil salinity poses a substantial threat to agricultural productivity, resulting in far-reaching consequences. Green-synthesized lignin nanoparticles (LNPs) have emerged as significant biopolymers which effectively promote sustainable crop production and enhance abiotic stress tolerance. However, the defensive role and underlying mechanisms of LNPs against salt stress in Zea mays remain unexplored. The present study aims to elucidate two aspects: firstly, the synthesis of lignin nanoparticles from alkali lignin, which were characterized using Field Emission Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM), Fourier Infrared Spectroscopy (FT-IR) and Energy Dispersive X-Ray Spectroscopy (EDX). The results confirmed the purity and morphology of LNPs. Secondly, the utilization of LNPs (200 mg/L) in nano priming to alleviate the adverse effects of NaCl (150 mM) on Zea mays seedlings. LNPs significantly reduced the accumulation of Na⁺ (17/21%) and MDA levels (21/28%) in shoots/roots while increased lignin absorption (30/31%), resulting in improved photosynthetic performance and plant growth. Moreover, LNPs substantially improved plant biomass, antioxidant enzymatic activities and upregulated the expression of salt-tolerant genes (ZmNHX3 (1.52 & 2.81 FC), CBL (2.83 & 3.28 FC), ZmHKT1 (2.09 & 4.87 FC) and MAPK1 (3.50 & 2.39 FC) in both shoot and root tissues. Additionally, SEM and TEM observations of plant tissues confirmed the pivotal role of LNPs in mitigating NaCl-induced stress by reducing damages to guard cells, stomata and ultra-cellular structures. Overall, our findings highlight the efficacy of LNPs as a practical and cost-effective approach to alleviate NaCl-induced stress in Zea mays plants. These results offer a sustainable agri-environmental strategy for mitigating salt toxicity and enhancing crop production in saline environments.

Keywords: Antioxidant defense system; Green synthesis; Lignin nanoparticles (LNPs); NaCl stress; Oxidative stress; Seed priming.

MeSH terms

Antioxidants* / metabolism
Green Chemistry Technology
Lignin* / chemistry
Nanoparticles* / chemistry
Nanoparticles* / toxicity
Photosynthesis / drug effects
Salinity
Salt Stress* / drug effects
Salt Tolerance / drug effects
Seedlings / drug effects
Zea mays* / drug effects

Substances

Lignin
Antioxidants