title: Vermicompost humic acids modulate the accumulation and metabolism of ROS in rice plants.
abstract: This work aims to determine the reactive oxygen species (ROS) accumulation, gene expression, anti-oxidant enzyme activity, and derived effects on membrane lipid peroxidation and certain stress markers (proline and malondialdehyde-MDA) in the roots of unstressed and PEG-stressed rice plants associated with vermicompost humic acid (VCHA) application. The results show that the application of VCHA to the roots of unstressed rice plants caused a slight but significant increase in root ROS accumulation and the gene expression and activity of the major anti-oxidant enzymes (superoxide dismutase and peroxidase). This action did not have negative effects on root development, and an increase in both root growth and root proliferation occurred. However, the root proline and MDA concentrations and the root permeability results indicate the development of a type of mild stress associated with VCHA application. When VCHA was applied to PEG-stressed plants, a clear alleviation of the inhibition in root development linked to PEG-mediated osmotic stress was observed. This was associated with a reduction in root ROS production and anti-oxidant enzymatic activity caused by osmotic stress. This alleviation of stress caused by VCHA was also reflected as a reduction in the PEG-mediated concentration of MDA in the root as well as root permeability. In summary, the beneficial action of VCHA on the root development of unstressed or PEG-stressed rice plants clearly involves the modulation of ROS accumulation in roots.
authors: Federal Rural University of Rio de Janeiro (Universidade Federal Rural do Rio de Janeiro-UFRRJ), Department of Soil, Soil Biology Laboratory, Rodovia BR 465km 7, Seropédica, RJ 23890-000, Brazil. Electronic address: cg.andres@gmail.com.
authors: Andrés Calderín
authors: AC
authors: García
authors: Federal Rural University of Rio de Janeiro (Universidade Federal Rural do Rio de Janeiro-UFRRJ), Department of Soil, Soil Biology Laboratory, Rodovia BR 465km 7, Seropédica, RJ 23890-000, Brazil. Electronic address: leoazevedo2001@yahoo.com.br.
authors: Leandro Azevedo
authors: LA
authors: Santos
authors: Federal Rural University of Rio de Janeiro (Universidade Federal Rural do Rio de Janeiro-UFRRJ), Department of Soil, Soil Biology Laboratory, Rodovia BR 465km 7, Seropédica, RJ 23890-000, Brazil. Electronic address: betdemolay@hotmail.com.
authors: Luiz Gilberto Ambrósio
authors: LG
authors: de Souza
authors: Federal Rural University of Rio de Janeiro (Universidade Federal Rural do Rio de Janeiro-UFRRJ), Department of Soil, Soil Biology Laboratory, Rodovia BR 465km 7, Seropédica, RJ 23890-000, Brazil. Electronic address: ochtavares@gmail.com.
authors: Orlando Carlos Huertas
authors: OC
authors: Tavares
authors: Federal Rural University of Rio de Janeiro (Universidade Federal Rural do Rio de Janeiro-UFRRJ), Department of Soil, Soil Biology Laboratory, Rodovia BR 465km 7, Seropédica, RJ 23890-000, Brazil. Electronic address: ezonta@ufrrj.br.
authors: Everaldo
authors: E
authors: Zonta
authors: Federal Rural University of Rio de Janeiro (Universidade Federal Rural do Rio de Janeiro-UFRRJ), Department of Soil, Soil Biology Laboratory, Rodovia BR 465km 7, Seropédica, RJ 23890-000, Brazil. Electronic address: ernane_floresta@yahoo.com.br.
authors: Ernane Tarcisio Martins
authors: ET
authors: Gomes
authors: Department of Environmental Biology, Agricultural Chemistry and Biology Group-CMI Roullier, Faculty of Sciences, University of Navarra, Spain. Electronic address: jgmina@timacagro.es.
authors: José Maria
authors: JM
authors: García-Mina
authors: Federal Rural University of Rio de Janeiro (Universidade Federal Rural do Rio de Janeiro-UFRRJ), Department of Soil, Soil Biology Laboratory, Rodovia BR 465km 7, Seropédica, RJ 23890-000, Brazil. Electronic address: rberbara@hotmail.com.
authors: Ricardo Luis Louro
authors: RL
authors: Berbara
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D006812:Humic Substances; D006861:Hydrogen Peroxide / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008315:Malondialdehyde / Q000378:metabolism; D012275:Oryza / Q000378:metabolism*; D009997:Osmotic Pressure; D018384:Oxidative Stress / Q000187:drug effects; D018517:Plant Roots / Q000378:metabolism; D011392:Proline / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D006812:Humic Substances; D017382:Reactive Oxygen Species; D008315:Malondialdehyde; D011392:Proline; D006861:Hydrogen Peroxide; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione
keywords: Humic substances; Osmotic stress; Reactive oxygen species