title: Alterations in lignin content and phenylpropanoids pathway in date palm (Phoenix dactylifera L.) tissues affected by brittle leaf disease.
abstract: Brittle leaf disease or Maladie de la Feuille Cassante (MFC) is a lethal disorder of date palm that has assumed epidemic proportions in the oases of Tunisia and Algeria. No pathogen could ever be associated with the disease, while leaflets of affected palms have been previously shown to be deficient in manganese. The work reported here aims to understand the biochemical basis of the date palm response to this disorder. Since the typical disease symptom is the leaf fragility, we have investigated lignin content in leaves and roots. Strong decrease in total lignin content was observed in affected leaves, while lignin content increased in affected roots. Histochemical analyses showed hyperlignification thicker suberin layer in roots cortical cells. The phenylpropanoids pathway was also disrupted in leaves and roots, cinnamoyl-CoA reductase and cinnamyl-alcohol dehydrogenase gene expression was affected by the disease which severely affects the cell wall integrity.
authors.affiliation: Laboratoire des Biotechnologies Végétales Appliquées à l'Amélioration des Cultures, Ecole Nationale d'Ingénieurs de Sfax, Route Soukra Km 4, Sfax, Tunisia. saiidimn@gmail.com
authors.forename: Mohammed Najib
authors.initials: MN
authors.lastname: Saidi
authors.forename: Donia
authors.initials: D
authors.lastname: Bouaziz
authors.forename: Ines
authors.initials: I
authors.lastname: Hammami
authors.forename: Ahmed
authors.initials: A
authors.lastname: Namsi
authors.forename: Noureddine
authors.initials: N
authors.lastname: Drira
authors.forename: Radhia
authors.initials: R
authors.lastname: Gargouri-Bouzid
mesh_terms: D000429:Alcohol Oxidoreductases / Q000235:genetics; D000445:Aldehyde Oxidoreductases / Q000235:genetics; D028023:Arecaceae / Q000737:chemistry / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D002473:Cell Wall / Q000378:metabolism; D016000:Cluster Analysis; D008031:Lignin / Q000032:analysis / Q000378:metabolism*; D008055:Lipids / Q000096:biosynthesis / Q000235:genetics; D010935:Plant Diseases; D018515:Plant Leaves / Q000737:chemistry / Q000166:cytology / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics*; D018517:Plant Roots / Q000737:chemistry / Q000166:cytology / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D020005:Propanols / Q000378:metabolism*
chemical_list: D008055:Lipids; D010940:Plant Proteins; D020005:Propanols; C439395:1-phenylpropanol; C065875:suberin; D008031:Lignin; D000429:Alcohol Oxidoreductases; C018656:cinnamyl alcohol dehydrogenase; D000445:Aldehyde Oxidoreductases; C019904:cinnamoyl CoA reductase
keywords: AIL; ASL; Brittle leaf disease; CAD; CCR; Date palm; Lignin analysis; MFC; Maladie de la Feuille Cassante (brittle leaf disease); Phenylpropanoids pathway; acid insoluble lignin; acid soluble lignin; cinnamoyl-CoA reductase; cinnamyl-alcohol dehydrogenase