title: Sulfonated graphene-induced hormesis is mediated through oxidative stress in the roots of maize seedlings.
abstract: The present study investigated the impact of sulfonated graphene (SG) on the growth of maize seedlings at a concentration range of 0-500mgL-1. Stress-related parameters including reactive oxygen species (ROS), intracellular Ca2+, antioxidant enzyme activities, lipid peroxidation, membrane leakage, cell death and root morphology were examined to reveal the potential mechanisms. The results indicate that SG induced a hormesis effect on plant height, i.e., low-concentration (50mgL-1) stimulation and high-concentration (500mgL-1) inhibition. The hormesis effect of SG on plant height was directly correlated with ROS levels in roots. A low concentration (50mgL-1) of SG promoted ROS scavenging, alleviated oxidative stress, enhanced the soluble protein (SP) content, and decreased intracellular Ca2+and cell death in the roots. At a higher concentration (500mgL-1), SG stimulated the generation of ROS in the roots, decreased SP content in the leaves, increased antioxidant enzyme activities, intracellular Ca2+, electrolyte leakage and cell death in the roots, and increased the malondialdehyde (MDA) content in both roots and leaves. Different changes were observed for root morphology at SG concentrations of 50 and 500mgL-1, and a larger amount of SG was deposited onto the root surface at a concentration of 500mgL-1compared with 50mgL-1.
authors: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
authors: Wenjie
authors: W
authors: Ren
authors: College of Resource and Environmental Engineering, Guizhou University, Guiyang 550025, China.
authors: Haiwei
authors: H
authors: Chang
authors: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China. Electronic address: yteng@issas.ac.cn.
authors: Ying
authors: Y
authors: Teng
mesh_terms: D004305:Dose-Response Relationship, Drug; D006108:Graphite / Q000009:adverse effects*; D059165:Hormesis / Q000187:drug effects*; D049329:Nanostructures / Q000009:adverse effects; D018384:Oxidative Stress; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development*; D036226:Seedlings / Q000187:drug effects / Q000254:growth & development; D003313:Zea mays / Q000187:drug effects / Q000254:growth & development*
chemical_list: D006108:Graphite
keywords: Cell death; Hormesis effect; Oxidative stress; ROS; Sulfonated graphene