Drivers of tree fecundity in pedunculate oak (Quercus robur) refugial populations at the species' southwestern range margin

Autor: Pedro Jordano, Arndt Hampe, Eva Moracho
Přispěvatelé: Estación Biológica de Doñana (EBD), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Biodiversité, Gènes & Communautés (BioGeCo), Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB)
Jazyk: angličtina
Rok vydání: 2018
Předmět:
Zdroj: Plant Biology
Plant Biology, Wiley, 2018, 20, pp.195-202. ⟨10.1111/plb.12578⟩
ISSN: 1435-8603
1438-8677
Popis: Rationale The current low-latitudinal range margins of many extra-tropical plant species consist of small and scattered populations that persist locally in microrefugia. It remains poorly understood how their refugial distribution affects mating patterns and reproductive success. Here we examine flower and acorn production and their determinants in refugial populations of the widespread European forest tree Pedunculate oak (Quercus robur). Methods We monitored male flower, female flower and acorn production in 159 adult trees from 12 oak stands over two years. We related these and derived parameters with a series of ecological and genetic predictor variables extrinsic (stand size, density and isolation as well as elevation, topography and forest cover) or intrinsic (size, phenology and several genotypic measures) to the target tree. Key results Tree fertility was unrelated with extrinsic factors but determined by tree size, although we detected size-independent variation in reproductive investment. Female flower number accurately predicted acorn crop size. Fruit set differed between years evidencing the existence of pollen limitation at the landscape but not at the local scale. Fruit set also tended to increase with the number of mates of the target tree. We detected no other evidences for genetic constraints on mating. Main conclusions Reproduction was triggered by a combination of small-scale and landscape-scale drivers. Although short-distance mating prevailed, limited pollen flow did not appear to significantly constrain reproductive success. The high intrinsic ability of populations to maintain their reproductive capacity may help explain their successful long-term persistence in an adverse broader environment. This article is protected by copyright. All rights reserved.
Databáze: OpenAIRE
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