title: Extraradical mycelium network of arbuscular mycorrhizal fungi allows fast colonization of seedlings under in vitro conditions.
abstract: Actively growing extraradical hyphae extending from mycorrhizal plants are an important source of inoculum in soils which has seldom been considered in vitro to inoculate young plantlets. Seedlings of Medicago truncatula were grown in vitro in the extraradical mycelium network extending from mycorrhizal plants. After 3, 6, 9, 12, and 15 days of contact with the mycelium, half of the seedlings were harvested and analyzed for root colonization. The other half was carefully transplanted in vitro on a suitable growth medium and mycelium growth and spore production were evaluated for 4 weeks. Seedlings were readily colonized after 3 days of contact with the mycelium. Starting from 6 days of contact, the newly colonized seedlings were able to reproduce the fungal life cycle, with the production of thousands of spores within 4 weeks. The fast mycorrhization process developed here opens the door to a broad range of in vitro studies for which either homogenous highly colonized seedlings or mass-produced in vitro inoculum is necessary.
authors.affiliation: Unité de Microbiologie, Université catholique de Louvain, Croix du Sud 3, 1348, Louvain-la-Neuve, Belgium.
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Voets
authors.affiliation: Unité de Microbiologie, Université catholique de Louvain, Croix du Sud 3, 1348, Louvain-la-Neuve, Belgium.
authors.forename: Ivan Enrique
authors.initials: IE
authors.lastname: de la Providencia
authors.affiliation: Unité de Microbiologie, Université catholique de Louvain, Croix du Sud 3, 1348, Louvain-la-Neuve, Belgium.|Instituto Nacional de Ciencias Agricolas (INCA), Km 3½ Carretera de Tapaste, Gaveta Postal 1, San José de Las Lajas, Havana, Cuba.
authors.forename: Kalyanne
authors.initials: K
authors.lastname: Fernandez
authors.affiliation: Unité de Microbiologie, Université catholique de Louvain, Croix du Sud 3, 1348, Louvain-la-Neuve, Belgium.
authors.forename: Marleen
authors.initials: M
authors.lastname: IJdo
authors.affiliation: Unité de Microbiologie, Mycothèque de l'Université Catholique de Louvain (MUCL), Université catholique de Louvain, Croix du Sud 3, 1348, Louvain-la-Neuve, Belgium.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Cranenbrouck
authors.affiliation: Unité de Microbiologie, Université catholique de Louvain, Croix du Sud 3, 1348, Louvain-la-Neuve, Belgium. stephan.declerck@uclouvain.be.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Declerck
mesh_terms: D046508:Culture Techniques; D055137:Glomeromycota / Q000254:growth & development*; D046913:Medicago truncatula / Q000254:growth & development / Q000382:microbiology*; D025282:Mycelium / Q000254:growth & development*; D038821:Mycorrhizae / Q000254:growth & development*; D018517:Plant Roots / Q000254:growth & development / Q000382:microbiology; D036226:Seedlings / Q000382:microbiology*; D013172:Spores, Fungal / Q000254:growth & development