RT Journal Article T1 Microgeographic variation in early fitness traits of Pinus sylvestris from contrasting soils A1 Jiménez Ramírez, Azucena A1 Solé Medina, Aida A1 Ramírez-Valiente, José A. A1 Robledo Arnuncio, Juan J. AB PremiseThe possibility of fine-scale intraspecific adaptive divergence under gene flow is established by theoretical models and has been confirmed empirically in tree populations distributed along steep altitudinal clines or across extreme edaphic discontinuities. However, the possibility of microgeographic adaptive divergence due to less severe but more frequent kinds of soil variation is unclear.MethodsIn this study, we looked for evidence of local adaptation to calcareous versus siliceous soil types in two nearby Mediterranean Pinus sylvestris populations connected via pollen flow. Using a greenhouse experiment, we tested for variation in early (up to three years of age) seedling performance among open-pollinated maternal families originating from each edaphic provenance when experimentally grown on both types of natural local substrate.ResultsAlthough seedlings were clearly affected by the edaphic environment, exhibiting lower and slower emergence as well as higher mortality on the calcareous than in the siliceous substrate, neither the performance on each substrate nor the plasticity among substrates varied significantly with seedling edaphic provenance.ConclusionsWe found no evidence of local adaptation to a non-extreme edaphic discontinuity over a small spatial scale, at least during early stages of seedling establishment. Future studies on microgeographic soil-driven adaptation should consider long-term experiments to minimize maternal effects and allow a potentially delayed expression of edaphic adaptive divergence. PB Wiley SN 0002-9122 YR 2023 FD 2023 LK https://hdl.handle.net/20.500.14352/91046 UL https://hdl.handle.net/20.500.14352/91046 LA eng NO Jiménez‐Ramírez, Azucena, et al. «Microgeographic Variation in Early Fitness Traits of Pinus Sylvestris from Contrasting Soils». American Journal of Botany, vol. 110, n.o 4, abril de 2023, p. e16159. https://doi.org/10.1002/ajb2.16159. NO Ministerio de Economía y Competitividad (España) NO Consejo Superior de Investigaciones Científicas NO European Commission DS Docta Complutense RD 21 mar 2026