title: Melatonin in Arabidopsis thaliana acts as plant growth regulator at low concentrations and preserves seed viability at high concentrations.
abstract: Since the discovery of melatonin in plants, several roles have been described for different species, organs, and developmental stages. Arabidopsis thaliana, being a model plant species, is adequate to contribute to the elucidation of the role of melatonin in plants. In this work, melatonin was monitored daily by UHPLC-MS/MS in leaves, in order to study its diurnal accumulation as well as the effects of natural and artificial light treatments on its concentration. Furthermore, the effects of exogenous application of melatonin to assess its role in seed viability after heat stress and as a regulator of growth and development of vegetative tissues were evaluated. Our results indicate that melatonin contents in Arabidopsis were higher in plants growing under natural radiation when compared to those growing under artificial conditions, and its levels were not diurnally-regulated. Exogenous melatonin applications prolonged seed viability after heat stress conditions. In addition, melatonin applications retarded leaf senescence. Its effects as growth promoter were dose and tissue-dependent; stimulating root growth at low concentrations and decreasing leaf area at high doses.
authors.affiliation: Instituto de Biología Agrícola de Mendoza (IBAM-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Mendoza, Argentina.
authors.forename: Ismaél Gatica
authors.initials: IG
authors.lastname: Hernández
authors.affiliation: Instituto de Biología Agrícola de Mendoza (IBAM-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Mendoza, Argentina.
authors.forename: Federico José Vicente
authors.initials: FJ
authors.lastname: Gomez
authors.affiliation: Instituto de Química de San Luis (INQUISAL-CONICET), Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, San Luis, Argentina.
authors.forename: Soledad
authors.initials: S
authors.lastname: Cerutti
authors.affiliation: Instituto Nacional de Tecnología Agropecuaria (INTA-Bariloche), Estación Experimental Agropecuaria Bariloche, CONICET, Río Negro, Argentina.
authors.forename: María Verónica
authors.initials: MV
authors.lastname: Arana
authors.affiliation: Instituto de Biología Agrícola de Mendoza (IBAM-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Mendoza, Argentina. Electronic address: msilva@fca.uncu.edu.ar.
authors.forename: María Fernanda
authors.initials: MF
authors.lastname: Silva
mesh_terms: D017360:Arabidopsis / Q000378:metabolism*; D008550:Melatonin / Q000378:metabolism*; D010937:Plant Growth Regulators / Q000378:metabolism*; D018515:Plant Leaves / Q000378:metabolism*; D012639:Seeds / Q000378:metabolism*
chemical_list: D010937:Plant Growth Regulators; D008550:Melatonin
keywords: Arabidopsis thaliana; Germination; Melatonin; Senescence; UHPLC-MS/MS