title: Expression of genes associated with the biosynthetic pathways of abscisic acid, gibberellin, and ethylene during the germination of lettuce seeds.
abstract: Seed germination and dormancy are complex phenomena that are controlled by many genes and environmental factors. Such genes are indicated by phytohormones that interact with each other, and may cause dormancy or promote seed germination. The objective of this study was to investigate gene expression associated with the biosynthetic pathways of abscisic acid (ABA), gibberellic acid (GA), and ethylene (ET) in dormant and germinated lettuce seeds. The expressions of LsNCED, LsGA3ox1, and ACO-B were evaluated in germinating and dormant seeds from the cultivars Everglades, Babá de Verão, Verônica, Salinas, Colorado, and Regina 71. The expressions of LsNCED, LsGA3ox1, and ACO-B were related to the biosynthesis of ABA, GA, and ET, respectively; therefore, the presence of these substances depends on genotype. LsNCED expression only occurred in dormant seeds, and was connected to dormancy. LsGA3ox1expression only occurred in germinated seeds, and was connected to germination. The ACO-B gene was involved in ET biosynthesis, and was expressed differently in germinated and dormant seeds, depending on the genotype, indicating different functions for different characteristics. Furthermore, sensitivity to phytohormones appeared to be more important than the expression levels of LsNCED, LsGA3ox1, or ACO-B.
authors.affiliation: Laboratório Central de Sementes, Departamento de Agricultura, Universidade Federal de Lavras, Lavras, MG, Brasil alineagrolavras@gmail.com.
authors.forename: A C S
authors.initials: AC
authors.lastname: Clemente
authors.affiliation: Laboratório Central de Sementes, Departamento de Agricultura, Universidade Federal de Lavras, Lavras, MG, Brasil.
authors.forename: R M
authors.initials: RM
authors.lastname: Guimarães
authors.affiliation: Departamento de Agricultura, Universidade Federal de São João Del Rei, Campus Sete Lagoas, MG, Brasil.
authors.forename: D C
authors.initials: DC
authors.lastname: Martins
authors.affiliation: Laboratório Central de Sementes, Departamento de Agricultura, Universidade Federal de Lavras, Lavras, MG, Brasil.
authors.forename: L A A
authors.initials: LA
authors.lastname: Gomes
authors.affiliation: Laboratório Central de Sementes, Departamento de Agricultura, Universidade Federal de Lavras, Lavras, MG, Brasil.
authors.forename: F
authors.initials: F
authors.lastname: Caixeta
authors.affiliation: Universidade do Estado do Mato Grosso, Nova Xavantina, MT, Brasil.
authors.forename: R G E
authors.initials: RG
authors.lastname: Reis
authors.affiliation: Embrapa Café, Brasília, DF, Brasil.
authors.forename: S D V F
authors.initials: SD
authors.lastname: Rosa
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism*; D005030:Ethylenes / Q000378:metabolism*; D015870:Gene Expression; D017343:Genes, Plant; D018525:Germination / Q000235:genetics*; D005875:Gibberellins / Q000378:metabolism*; D018545:Lactuca / Q000196:embryology* / Q000235:genetics; D012639:Seeds / Q000254:growth & development* / Q000378:metabolism
chemical_list: D005030:Ethylenes; D005875:Gibberellins; D000040:Abscisic Acid; C036216:ethylene