title: Early histological, hormonal, and molecular changes during pineapple (Ananas comosus (L.) Merrill) artificial flowering induction.
abstract: Natural flowering can cause serious scheduling problems in the pineapple (Ananas comosus) industry and increase harvest costs. Pineapple flowering is thought to be triggered by increased ethylene levels and artificial forcing of pineapple flowering is a common practice to promote flowering synchronisation. However, little is known about the early hormonal and molecular changes of pineapple flowering induction and development. Here, we aimed to analyse the molecular, hormonal, and histological changes during artificial pineapple flowering by Ethrel®48 treatment. Histological analyses of the shoot apical meristem, leaf gibberellic acid (GA3), and ethylene quantification were carried out during the first 72h after Ethrel®48 treatment. Expression profiles from ethylene biosynthesis (AcACS2 and AcACO1), gibberellin metabolism (AcGA2-ox1 and AcDELLA1), and flower development (FT-like gene (AcFT), LFY-like gene (AcLFY), and a PISTILLATA-like gene (AcPI)) genes were analysed during the first 24h after Ethrel®48 treatment. Differentiation processes of the shoot apical meristem into flower buds were already present in the first 72h after Ethrel®48 treatment. Ethrel®48 lead to a reduction in GA3levels, probably triggered by elevated ethylene levels and the positive regulation AcGA2-ox1. AcLFY activation upon Ethrel®48 may also have contributed to the reduction of GA3levels and, along with the up-regulation of AcPI, are probably associated with the flower induction activation. AcFT and AcDELLA1 do not seem to be regulated by GA3and ethylene. Decreased GA3and increased ethylene levels suggest an accumulation of AcDELLA1, which may display an important role in pineapple flowering induction. Thus, this study shows that molecular, hormonal, and histological changes are present right after Ethrel®48 treatment, providing new insights into how pineapple flowering occurs under natural conditions.
authors.affiliation: Department of Basic and Specifics Sciences, University of Ciego de Ávila, Cuba.
authors.forename: Maita Eulalia Ávila
authors.initials: MEÁ
authors.lastname: Espinosa
authors.affiliation: Plant Molecular Physiology Laboratory, Biology Department, Federal University of Lavras (UFLA), Lavras, Minas Gerais, Brazil.
authors.forename: Rafael Oliveira
authors.initials: RO
authors.lastname: Moreira
authors.affiliation: Plant Molecular Physiology Laboratory, Biology Department, Federal University of Lavras (UFLA), Lavras, Minas Gerais, Brazil.
authors.forename: André Almeida
authors.initials: AA
authors.lastname: Lima
authors.affiliation: Federal University of Tocantins (UFT), Campus de Palmas, Palmas, Tocantins, Brazil.
authors.forename: Solange Aparecida
authors.initials: SA
authors.lastname: Ságio
authors.affiliation: Federal University of Tocantins (UFT), Campus Universitário de Gurupi, Gurupi, Tocantins, Brazil.
authors.forename: Horllys Gomes
authors.initials: HG
authors.lastname: Barreto
authors.affiliation: Department of Basic and Specifics Sciences, University of Ciego de Ávila, Cuba.
authors.forename: Sara Lazara Pérez
authors.initials: SLP
authors.lastname: Luiz
authors.affiliation: Bioplant Center, University of Ciego de Ávila, Cuba.
authors.forename: Carlos Eduardo Aragón
authors.initials: CEA
authors.lastname: Abreu
authors.affiliation: Bioplant Center, University of Ciego de Ávila, Cuba.
authors.forename: Ermis
authors.initials: E
authors.lastname: Yanes-Paz
authors.affiliation: Bioplant Center, University of Ciego de Ávila, Cuba.
authors.forename: Yanelis Capdesuñer
authors.initials: YC
authors.lastname: Ruíz
authors.affiliation: Bioplant Center, University of Ciego de Ávila, Cuba.
authors.forename: Justo Lorenzo
authors.initials: JL
authors.lastname: González-Olmedo
authors.affiliation: Plant Molecular Physiology Laboratory, Biology Department, Federal University of Lavras (UFLA), Lavras, Minas Gerais, Brazil. Electronic address: chalfunjunior@dbi.ufla.br.
authors.forename: Antonio
authors.initials: A
authors.lastname: Chalfun-Júnior
mesh_terms: D000595:Amino Acid Sequence; D031230:Ananas / Q000033:anatomy & histology* / Q000166:cytology* / Q000235:genetics; D005030:Ethylenes / Q000378:metabolism; D035264:Flowers / Q000502:physiology*; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005875:Gibberellins / Q000378:metabolism; D010937:Plant Growth Regulators / Q000378:metabolism*; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D005030:Ethylenes; D005875:Gibberellins; D010937:Plant Growth Regulators; D010940:Plant Proteins; C036216:ethylene; C007842:gibberellic acid
keywords: Apical meristem; DELLA; Ethrel(®)48; Ethylene; Gibberellins; RT-qPCR