title: Integrative effects of zinc and temperature on germination in Dimorphandra wilsonii rizz.: Implications of climate changes.
abstract: The integrative effects of zinc (Zn; 0 mg L-1, 75 mg L-1, 150 mg L-1, and 200 mg L-1) and temperature (25 °C, 30 °C, and 35 °C) on seed germination of the threatened Brazilian species Dimorphandra wilsonii were evaluated. Zinc effects on seed germination were only observed at 30 °C and 35 °C. By stimulating respiration rates, rising temperatures accentuate hydrogen peroxide (H2O2) formation in germinating seeds in the presence of Zn. Seed Zn tolerance was related to the activation of enzymatic antioxidants, and ascorbate peroxidase (APX) activity had a central role in H2O2scavenging under the highest temperatures tested. Increased APX activity allowed successful germination, whereas decreasing APX activity was accompanied by decreasing germination rates in Zn-treated seeds at 35 °C. Within a scenario of future climate change, it will be extremely important to avoid increasing Zn concentrations in natural habitats that would threaten conservation efforts directed toward this endangered plant species. Environ Toxicol Chem 2017;36:2036-2042. © 2017 SETAC.
authors.affiliation: Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Pampulha, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Elisa Monteze
authors.initials: EM
authors.lastname: Bicalho
authors.affiliation: Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Pampulha, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Marcelo Pedrosa
authors.initials: MP
authors.lastname: Gomes
authors.affiliation: Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Pampulha, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Ailton Gonçalves
authors.initials: AG
authors.lastname: Rodrigues-Junior
authors.affiliation: Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Pampulha, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Túlio Gabriel Soares
authors.initials: TGS
authors.lastname: Oliveira
authors.affiliation: Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Pampulha, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Cintia de Almeida
authors.initials: CA
authors.lastname: Gonçalves
authors.affiliation: Departamento de Jardim Botânico, Fundação Zoo-Botânica de Belo Horizonte, Pampulha, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Marcia Bacelar
authors.initials: MB
authors.lastname: Fonseca
authors.affiliation: Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Pampulha, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Queila Souza
authors.initials: QS
authors.lastname: Garcia
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D001938:Brazil; D057231:Climate Change; D007887:Fabaceae / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D018525:Germination / Q000187:drug effects*; D006358:Hot Temperature; D006861:Hydrogen Peroxide / Q000378:metabolism; D010084:Oxidation-Reduction; D012639:Seeds / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D012989:Soil Pollutants / Q000633:toxicity*; D015032:Zinc / Q000633:toxicity*
chemical_list: D000975:Antioxidants; D012989:Soil Pollutants; D006861:Hydrogen Peroxide; D015032:Zinc
keywords: Antioxidants; Climate changes; Respiration; Toxic effects; Trace elements