title: Local adaptation in migrated interior Douglas-fir seedlings is mediated by ectomycorrhizas and other soil factors.
abstract: Separating edaphic impacts on tree distributions from those of climate and geography is notoriously difficult. Aboveground and belowground factors play important roles, and determining their relative contribution to tree success will greatly assist in refining predictive models and forestry strategies in a changing climate. In a common glasshouse, seedlings of interior Douglas-fir (Pseudotsuga menziesii var. glauca) from multiple populations were grown in multiple forest soils. Fungicide was applied to half of the seedlings to separate soil fungal and nonfungal impacts on seedling performance. Soils of varying geographic and climatic distance from seed origin were compared, using a transfer function approach. Seedling height and biomass were optimized following seed transfer into drier soils, whereas survival was optimized when elevation transfer was minimised. Fungicide application reduced ectomycorrhizal root colonization by c. 50%, with treated seedlings exhibiting greater survival but reduced biomass. Local adaptation of Douglas-fir populations to soils was mediated by soil fungi to some extent in 56% of soil origin by response variable combinations. Mediation by edaphic factors in general occurred in 81% of combinations. Soil biota, hitherto unaccounted for in climate models, interacts with biogeography to influence plant ranges in a changing climate.
authors.affiliation: Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Pickles
authors.affiliation: UC Cooperative Extension, Humboldt and Del Norte Counties, Eureka, CA, 95503, USA.
authors.forename: Brendan D
authors.initials: BD
authors.lastname: Twieg
authors.affiliation: Kalamalka Research Station, BC Ministry of Forests, Lands and Natural Resource Operations, 3401 Reservoir Road, Vernon, BC, V1B 2C7, Canada.
authors.forename: Gregory A
authors.initials: GA
authors.lastname: O'Neill
authors.affiliation: Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada.
authors.forename: William W
authors.initials: WW
authors.lastname: Mohn
authors.affiliation: Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
authors.forename: Suzanne W
authors.initials: SW
authors.lastname: Simard
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects; D000704:Analysis of Variance; D000935:Antifungal Agents / Q000494:pharmacology; D018533:Biomass; D001955:British Columbia; D002980:Climate; D015169:Colony Count, Microbial; D005843:Geography; D038821:Mycorrhizae / Q000187:drug effects / Q000254:growth & development / Q000502:physiology*; D028224:Pseudotsuga / Q000187:drug effects / Q000382:microbiology*; D012044:Regression Analysis; D036226:Seedlings / Q000187:drug effects / Q000254:growth & development / Q000382:microbiology*; D012987:Soil
chemical_list: D000935:Antifungal Agents; D012987:Soil
keywords: Pseudotsuga menziesii var. glauca (interior Douglas-fir); assisted migration; ectomycorrhizal fungi (EMF); edaphic factors; forestry; fungicide; local adaptation; seed transfer