title: Mycorrhizal compatibility and symbiotic seed germination of orchids from the Coastal Range and Andes in south central Chile.
abstract: Little is known about Orchidaceae plants in Chile and their mycorrhizal associations, a key issue for designing protective actions for endangered species. We investigated root fungi from seven terrestrial orchid species to identify potential mycorrhizal fungi. The main characteristics of Rhizoctonia-like fungi were observed under light microscopy, and isolates were identified through PCR-ITS sequencing. Molecular identification of fungal sequences showed a high diversity of fungi colonizing roots. Fungal ability to germinate seeds of different orchids was determined in symbiotic germination tests; 24 fungal groups were isolated, belonging to the genera Tulasnella, Ceratobasidium, and Thanatephorus. Furthermore, dark septate and other endophytic fungi were identified. The high number of Rhizoctonia-like fungi obtained from adult orchids from the Coastal mountain range suggests that, after germination, these orchids may complement their nutritional demands through mycoheterotrophy. Nonetheless, beneficial associations with other endophytic fungi may also co-exist. In this study, isolated mycorrhizal fungi had the ability to induce seed germination at different efficiencies and with low specificity. Germin ation rates were low, but protocorms continued to develop for 60 days. A Tulasnella sp. isolated from Chloraea gavilu was most effective to induce seed germination of different species. The dark septate endophytic (DSE) fungi did not show any effect on seed development; however, their widespread occurrence in some orchids suggests a putative role in plant establishment.
authors: Departamento de Ciencias Forestales, Laboratorio de Biorremediación, Facultad de Ciencias Agropecuarias y Forestales, Universidad de La Frontera, Av. Francisco Salazar, 01145, Temuco, Chile.
authors: Hector
authors: H
authors: Herrera
authors: Vale Institute of Technology - Sustainable Development, Rua Boaventura da silva 955, Cep 66050-090, Belém, PA, Brazil.
authors: Rafael
authors: R
authors: Valadares
authors: Facultad de Ciencias Básicas, Universidad Católica del Maule, Avenida San Miguel 3605, Casilla 617, Talca, Chile.
authors: Domingo
authors: D
authors: Contreras
authors: The Bashan Institute of Science, 1730 Post Oak Court, Auburn, AL, 36830, USA.|Department of Entomology and Plant Pathology, Auburn University, 301 Funchess Hall, Auburn, AL, 36849, USA.|Environmental Microbiology Group, Northwestern Center for Biological Research (CIBNOR), Av. IPN 195, La Paz, B.C.S. 23096, Mexico.
authors: Yoav
authors: Y
authors: Bashan
authors: Departamento de Ciencias Forestales, Laboratorio de Biorremediación, Facultad de Ciencias Agropecuarias y Forestales, Universidad de La Frontera, Av. Francisco Salazar, 01145, Temuco, Chile. cesar.arriagada@ufrontera.cl.
authors: Cesar
authors: http://orcid.org/0000-0002-8549-6302
authors: C
authors: Arriagada
mesh_terms: D002677:Chile; D004271:DNA, Fungal / Q000032:analysis; D056727:Endangered Species; D018525:Germination; D038821:Mycorrhizae / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D029595:Orchidaceae / Q000254:growth & development / Q000382:microbiology*; D010802:Phylogeny; D018517:Plant Roots / Q000382:microbiology; D012639:Seeds / Q000254:growth & development* / Q000382:microbiology; D017422:Sequence Analysis, DNA; D013559:Symbiosis
chemical_list: D004271:DNA, Fungal
keywords: Orchid mycorrhiza; Rhizoctonia-like fungi; Root fungal endophytes; Symbiotic germination