Title :

Fine-scale genetic structure in the orchid Gymnadenia conopsea is not associated with local density of flowering plants

Author(s) :

Sletvold, Nina [Auteur]
Uppsala Universitet [Uppsala]
Joffard, Nina [Auteur]
Uppsala Universitet [Uppsala]
Évolution, Écologie et Paléontologie (Evo-Eco-Paleo) - UMR 8198 [Evo-Eco-Paléo (EEP)]
Söderquist, Linus [Auteur]
Uppsala Universitet [Uppsala]

Journal title :

American Journal of Botany

Publisher :

Botanical Society of America

Publication date :

2024

ISSN :

0002-9122

English keyword(s) :

coancestry
density-dependence
fine-scale genetic structure
gene flow
kinship
local density
Orchidaceae
pollen dispersal
relatedness
seed dispersal

HAL domain(s) :

Sciences du Vivant [q-bio]/Génétique/Génétique des plantes
Sciences du Vivant [q-bio]/Génétique/Génétique des populations [q-bio.PE]

English abstract : [en]

Premise: Density-dependent pollinator visitation can lead to density-dependent mating patterns and within-population genetic structure. In Gymnadenia conopsea, individuals in low-density patches receive more self pollen ...
Show more >Premise: Density-dependent pollinator visitation can lead to density-dependent mating patterns and within-population genetic structure. In Gymnadenia conopsea, individuals in low-density patches receive more self pollen than individuals in highdensity patches, suggesting higher relatedness at low density. Ongoing fragmentation is also expected to cause more local matings, potentially leading to biparental inbreeding depression.Methods: To evaluate whether relatedness decreases with local density, we analyzed 1315 SNP loci in 113 individuals within two large populations. We quantified withinpopulation genetic structure in one of the populations, recorded potential habitat barriers, and visualized gene flow using estimated effective migration surfaces (EEMS). We further estimated the magnitude of biparental inbreeding depression that would result from matings restricted to within 5 m.Results: There was no significant relationship between local density and relatedness in any population. We detected significant fine-scale genetic structure consistent with isolation by distance, with positive kinship coefficients at distances below 10 m. Kinship coefficients were low, and predicted biparental inbreeding depression resulting from matings within the closest 5 m was a modest 1-3%. The EEMS suggested that rocks and bushes may act as barriers to gene flow within a population.Conclusions: The results suggest that increased self-pollen deposition in sparse patches does not necessarily cause higher selfing rates or that inbreeding depression results in low establishment success of inbred individuals. The modest relatedness suggests that biparental inbreeding depression is unlikely to be an immediate problem following fragmentation of large populations. The results further indicate that habitat structure may contribute to governing fine-scale genetic structure in G. conopsea.Show less >

Language :

Anglais

Popular science :

Non

Collections :

• Évolution, Écologie et Paléontologie (Evo Eco Paleo) - UMR 8198

Source :

Harvested from HAL