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Diversité Des Populations De Xanthomonas Phaseoli Pv

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Diversité Des Populations De Xanthomonas Phaseoli Pv Diversité des populations de Xanthomonas phaseoli pv. manihotis au Mali et recherche de sources de résistance durables chez le manioc Moussa Kante To cite this version: Moussa Kante. Diversité des populations de Xanthomonas phaseoli pv. manihotis au Mali et recherche de sources de résistance durables chez le manioc. Sciences agricoles. Université Montpellier; Université de Bamako. Institut Supérieur de Formation et de Recherche Appliquée, 2020. Français. NNT : 2020MONTG028. tel-03157340 HAL Id: tel-03157340 https://tel.archives-ouvertes.fr/tel-03157340 Submitted on 3 Mar 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. THÈSE POUR OBTENIR LE GRADE DE DOCTEUR DE L’UNIVERSITÉ DE M ONTPELLIER En Mécanisme des Interactions Parasitaires École doctorale GAIA Unité de recherche IPME En partenariat international avec IPU Ex-ISFRA & Université de Ségou, MALI Diversité des populations de Xanthomonas phaseoli pv manihotis (Xpm ) au Mali et recherche de source de résistance durable chez le manioc. Présentée par Moussa KANTE Rapport de gestion Le 17 Décembre 2020 Sous la direction de Boris SZUREK, Directeur de thèse et Ousmane KOITA, Co-Directeur de thèse 2015 Devant le jury composé de Dr Haby SANOU, Directeur de Recherche, Institut d’Economie Rurale/IER -Bamako Présidente Prof. Claude BRAGARD, Professeur d’Université, Université Catholique de Louvain Rapporteur Dr Soungalo SARRA, Directeur de Recherche, Institut d’Economie Rurale/IER -Niono-Ségou Examinateur Prof. Cla ire NEEMA, Professeur d’Université, Montpellier SupAgro Examinatrice Prof. Ousmane KOITA, Professeur d’Université, USTTB -Bamako Co-directeur de Thèse Dr Boris SZUREK, Directeur de Recherche, IRD-Montpellier Directeur de Thèse TABLES DES MATIERES TABLES DES MATIERES ..................................................................................................................... i RESUME .......................................................................................................................................... v ABSTRACT ...................................................................................................................................... vi REMERCIEMENTS .......................................................................................................................... vii LISTE DES FIGURES .......................................................................................................................... x LISTE DES TABLEAUX ..................................................................................................................... xii LISTE DES ENCADRÉS .................................................................................................................... xiii LISTE DES ANNEXES ...................................................................................................................... xiv LISTE DES SIGLES ET ABREVIATIONS ............................................................................................... xv CHAPITRE 1 : INTRODUCTION GENERALE ......................................................................................... 1 Préambule : De l’importance de l’étude des populati ons phytopathogènes pour un développement agricole durable. .................................................................................................................................. 1 Partie 1-Epidémiologie moléculaire : comprendre les facteurs favorisant les épidémies pour mieux en maitriser les impacts ...................................................................................................................... 5 1.1-De l’espèce à la population bactérienne : ..................................................................................... 6 1.2-Aspects clés de la génétique des populations et de l’épidémiologie moléculaire ....................... 8 1.2.1-Forces évolutives qui influencent la génétique des populations ......................................... 10 1.2.2-Outils d’études de l’épidémiologie moléculaire .................................................................. 12 1.3-Types de marqueurs moléculaires .............................................................................................. 13 1.3.1-Marqueur moléculaire VNTR, technique de génotypage de MVLA ..................................... 18 1.3.2-Avantages et limites de la technique MLVA ........................................................................ 22 Partie 2-Les interactions plante-pathogène et mécanismes d’action des phytobactéries ............... 24 2.1-Comportement de la plante et du pathogène lors d’une interaction ........................................ 26 2.1.1-Généralités ........................................................................................................................... 28 2.1.2-L’hypothèse de la relation « gène pour gène » ................................................................... 29 2.2-Les effecteurs : facteurs de pathogénie et éliciteurs .................................................................. 30 2.2.1-Facteurs de pathogenèse chez les phytobactéries .............................................................. 30 2.2.2-Système de sécrétion de type III et effecteurs de type III ................................................... 31 2.2.3-Les effecteurs de type III : TALEs (cas particulier des Xanthomonas) .................................. 34 2.2.4-Les effecteurs TALs chez les Xanthomonas .......................................................................... 35 2.3-Résistance des plantes ................................................................................................................ 39 2.3.1-Reconnaissance et déclenchement des réactions de défense ............................................ 39 2.3.2-Mécanismes de défense constitutive et induite .................................................................. 43 i Moussa KANTE, Manuscrit de these « le manioc et Xpm au Mali », Dec-2020 2.3.3-Types de résistance .............................................................................................................. 48 Partie 3 - Le modèle d’étude : Le pathosystème Xanthomonas phaseoli pv. manihotis et son impact sur la culture du manioc ( Manihot esculenta L. Crantz) .................................................................. 51 3.1-Le manioc .................................................................................................................................... 52 3.1.1-Morphologie de la plante de manioc ................................................................................... 54 3.1.2-Conditions optimales de développement de la culture du manioc ..................................... 54 3.1.3-Origine et distribution du manioc ........................................................................................ 55 3.1.4-Importance de la culture ...................................................................................................... 55 3.1.5-Management de la culture de Manioc ................................................................................. 60 3.2-Le manioc au Mali ....................................................................................................................... 68 3.2.1-Statut actuel de la production du manioc au Mali : statistique et évolution actuelle ........ 70 3.2.2-Zone de production au Mali ................................................................................................. 72 3.2.3-Contraintes de production et leur gestion ........................................................................... 73 3.3-La bactériose vasculaire du manioc causée par Xanthomonas phaseoli pv. manihotis ............ 93 3.3.1-Impact, importance de la maladie ....................................................................................... 93 3.3.2-Xanthomonas phaseoli pv. manihotis: ................................................................................. 96 3.3.3-Symtomatologie de la bactériose vasculaire du manioc: .................................................. 100 3.3.4-Epidemiologie : Condition favorable et dissémination de la bactériose vasculaire du manioc ......................................................................................................................................... 100 3.3.5-Epidemiologie : Cycle de la maladie ................................................................................... 102 3.3.6-Epidemiologie moléculaire appliquée à Xpm ..................................................................... 106 3.3.7- Gestion de la bactériose vasculaire du manioc ................................................................. 109 Partie 4-Présentation du sujet de la thèse ................................................................................... 113 4.1-Approche et Problématique du sujet de la thèse ..................................................................... 113 4.2-Questions de recherche : .........................................................................................................
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