title: Brittle leaf disease induces an oxidative stress and decreases the expression of manganese-related genes in date palm (Phoenix dactylifera L.).
abstract: In Tunisia, date orchards are being decimated by a disease called brittle leaf disease of unknown origin. Previous studies reported that affected soils, roots and leaves were manganese deficient. In this study, we investigated the biochemical and molecular response of MFC-affected date palms to the oxidative stress generated by manganese deficiency. Both the malondialdehyde (MDA) content which is indicative of lipid peroxidation and the activities of antioxidant enzyme were measured in affected leaves and roots. The expression profiles of oxidative stress-related genes encoding superoxide dismutases and peroxidases were also investigated. The data show that the MDA concentration increased but not significantly in affected leaves. However, such MDA increase was significant in roots of MFC-affected plants. The total superoxide dismutase (SOD) activity increased in affected leaves and roots, while RT-PCR experiments showed that MnSOD RNA decreased in affected leaves and roots unlike FeSOD and Cu/Zn-SOD RNA expression increased in these organs. In addition ascorbate peroxidase (APx) and glutathione peroxidase (GPx) RNA expression increased in diseased leaves and roots.
authors.affiliation: Laboratoire des Biotechnologies Végétales Appliquées à l'Amélioration des Cultures, Ecole Nationale d'Ingénieurs de Sfax, Route Soukra Km 4, B.P 1173, 3038 Sfax, Tunisia. saiidimn@gmail.com
authors.forename: Mohammed Najib
authors.initials: MN
authors.lastname: Saidi
authors.forename: Rania
authors.initials: R
authors.lastname: Jbir
authors.forename: Imen
authors.initials: I
authors.lastname: Ghorbel
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: D000975:Antioxidants / Q000378:metabolism; D028023:Arecaceae / Q000235:genetics / Q000378:metabolism*; D060387:Ascorbate Peroxidases / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D017343:Genes, Plant; D005979:Glutathione Peroxidase / Q000235:genetics / Q000378:metabolism; D015227:Lipid Peroxidation / Q000502:physiology; D008315:Malondialdehyde / Q000378:metabolism*; D008345:Manganese / Q000172:deficiency*; D018384:Oxidative Stress / Q000235:genetics*; D010935:Plant Diseases / Q000235:genetics*; D018515:Plant Leaves / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D012313:RNA / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism*; D014416:Tunisia
chemical_list: D000975:Antioxidants; D008345:Manganese; D008315:Malondialdehyde; D012313:RNA; D060387:Ascorbate Peroxidases; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase