title: Effect of lead on root growth.
abstract: Lead (Pb) is one of the most widespread heavy metal contaminant in soils. It is highly toxic to living organisms. Pb has no biological function but can cause morphological, physiological, and biochemical dysfunctions in plants. Plants have developed a wide range of tolerance mechanisms that are activated in response to Pb exposure. Pb affects plants primarily through their root systems. Plant roots rapidly respond either (i) by the synthesis and deposition of callose, creating a barrier that stops Pb entering (ii) through the uptake of large amounts of Pb and its sequestration in the vacuole accompanied by changes in root growth and branching pattern or (iii) by its translocation to the aboveground parts of plant in the case of hyperaccumulators plants. Here we review the interactions of roots with the presence of Pb in the rhizosphere and the effect of Pb on the physiological and biochemical mechanisms of root development.
authors.affiliation: Laboratoire de Physiologie et Biotechnologie Végétale, Faculté des Sciences, Université Mohammed V - Agdal Rabat, Morocco ; Laboratoire de Biotechnologie des Plantes, Centre National de l'Energie, des Sciences et des Techniques Nucléaires, Unité de Biologie et Recherches Médicales- Division Sciences du Vivant Rabat, Morocco ; Equipe Rhizogenèse, Institut de Recherche pour le Développement, Unité Mixte de Recherche Diversité Adaptation et Developpement des Plantes,Université Montpellier 2 Montpellier, France.
authors.forename: Mouna
authors.initials: M
authors.lastname: Fahr
authors.forename: Laurent
authors.initials: L
authors.lastname: Laplaze
authors.forename: Najib
authors.initials: N
authors.lastname: Bendaou
authors.forename: Valerie
authors.initials: V
authors.lastname: Hocher
authors.forename: Mohamed El
authors.initials: ME
authors.lastname: Mzibri
authors.forename: Didier
authors.initials: D
authors.lastname: Bogusz
authors.forename: Abdelaziz
authors.initials: A
authors.lastname: Smouni
keywords: lead; root; root development; tolerance; uptake