Incomplete partitioning of pollinators by Linum suffruticosum and its coflowering congeners
Metadata
Show full item recordEditorial
Wiley
Materia
Character displacement Heterostyly Inaccuracy Interspecific pollen transfer Linaceae Pollen tube Pollination ecotypes Pollinator importance Reproductive interference
Date
2023-05-10Referencia bibliográfica
Pérez‐Barrales, R., and W. S. Armbruster. 2023. Incomplete partitioning of pollinators by Linum suffruticosum and its coflowering congeners. American Journal of Botany 110(6): e16181. [https://doi.org/10.1002/ajb2.16181]
Sponsorship
Royal Society 13525; Spanish Ministry of Science and Innovation by MCIN/AEI PID2021-127264NB-I00; National Science Foundation (NSF) DEB-0444754; Universidad de Granada/CBUAAbstract
PremiseLinum suffruticosum shows variations in pollinator fit, pollen pickup, and local pollinators that predict pollen deposition rates. The species often coflowers with other Linum species using the same pollinators. We investigated whether L. suffruticosum trait variation could be explained by local patterns of pollinator sharing and associated evolution to reduce interspecific pollen transfer. MethodsPollinator observations were made in different localities (single species, coflowering with other congeners). Floral traits were measured to detect differences across populations and from coflowering species. Reproductive costs were quantified using interspecific hand pollinations and measures of pollen-tube formation, combined with observations of pollen arrival on stigmas and pollen-tube formation after natural pollination in allopatric and sympatric localities. ResultsThe size and identity of the most important pollinator of L. suffruticosum and whether there was pollinator sharing with coflowering species appeared to explain floral trait variation related to pollinator fit. The morphological overlap of the flowers of L. suffruticosum with those of coflowering species varied, depending on coflowering species identity. A post-pollination incompatibility system maintains reproductive isolation, but conspecific pollen-tube formation was lower after heterospecific pollination. Under natural pollination at sites of coflowering with congeners, conspecific pollen-tube formation was lower than at single-species localities. ConclusionsTrait variation in L. suffruticosum appears to respond to the most important local pollinator. Locally, incomplete pollinator partitioning might cause interspecific pollination, imposing reproductive costs. These reproductive costs may generate selection on floral traits for reduced morphological overlap with coflowering congeners, leading to the evolution of pollination ecotypes.