title: Increase of Fungal Pathogenicity and Role of Plant Glutamine in Nitrogen-Induced Susceptibility (NIS) To Rice Blast.
abstract: HighlightModifications in glutamine synthetase OsGS1-2 expression and fungal pathogenicity underlie nitrogen-induced susceptibility to rice blast. Understanding why nitrogen fertilization increase the impact of many plant diseases is of major importance. The interaction betweenMagnaporthe oryzaeand rice was used as a model for analyzing the molecular mechanisms underlying Nitrogen-Induced Susceptibility (NIS). We show that our experimental system in which nitrogen supply strongly affects rice blast susceptibility only slightly affects plant growth. In order to get insights into the mechanisms of NIS, we conducted a dual RNA-seq experiment on rice infected tissues under two nitrogen fertilization regimes. On the one hand, we show that enhanced susceptibility was visible despite an over-induction of defense gene expression by infection under high nitrogen regime. On the other hand, the fungus expressed to high levels effectors and pathogenicity-related genes in plants under high nitrogen regime. We propose that in plants supplied with elevated nitrogen fertilization, the observed enhanced induction of plant defense is over-passed by an increase in the expression of the fungal pathogenicity program, thus leading to enhanced susceptibility. Moreover, some rice genes implicated in nitrogen recycling were highly induced during NIS. We further demonstrate that theOsGS1-2glutamine synthetase gene enhances plant resistance toM. oryzaeand abolishes NIS and pinpoint glutamine as a potential key nutrient during NIS.
authors.affiliation: State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University Kunming, China.
authors.forename: Huichuan
authors.initials: H
authors.lastname: Huang
authors.affiliation: Faculty of Agronomy, Hue University of Agriculture and Forestry Hue, Vietnam.
authors.forename: Thuy
authors.initials: T
authors.lastname: Nguyen Thi Thu
authors.affiliation: State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China, Yunnan Agricultural University Kunming, China.
authors.forename: Xiahong
authors.initials: X
authors.lastname: He
authors.affiliation: UMR1349 IGEPP, Université Rennes 1 Rennes, France.
authors.forename: Antoine
authors.initials: A
authors.lastname: Gravot
authors.affiliation: INRA, UMR1332, Biologie du Fruit et Pathologie, Plateforme Métabolome de Bordeaux Villenave d'Ornon, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Bernillon
authors.affiliation: SupAgro, UMR BGPI Institut National de la Recherche Agronomique/CIRAD/SupAgro, Campus International de Baillarguet Montpellier, France.
authors.forename: Elsa
authors.initials: E
authors.lastname: Ballini
authors.affiliation: Institut National de la Recherche Agronomique, UMR BGPI Institut National de la Recherche Agronomique/CIRAD/SupAgro, Campus International de Baillarguet Montpellier, France.
authors.forename: Jean-Benoit
authors.initials: JB
authors.lastname: Morel
keywords: Magnaporthe oryzae; defense; effector; fertilizer; glutamine; nitrogen; pathogenicity; rice