Stabilizing selection on nectar concentration in wild Petunia axillaris, as revealed by genetic analysis of pollen dispersal

Authors
Gleiser, Gabriela Laura; Internicola, Antonina I.; Austerlitz, Frédéric; Bernasconi, Giorgina
Publication Year
2014
Language
English
Format
article
Status
Published version
Description
Most animal-pollinated plants produce nectar as a pollinator reward. Despite the main role that nectar plays in plant-pollinator interactions, the impact of natural variation in nectar traits on realized male fitness is poorly known. Here, we assessed this relation for a wild Petunia axillaris population using paternity-based direct selection gradient analysis, which allowed us also to infer pollen dispersal patterns. Because male fecundity may depend on other traits which could be associated with nectar characteristics (i.e. volume and concentration), we also considered selection on other key reproductive traits. The analysis revealed that P. axillaris was a strict outcrosser, but that successful pollination occurred mainly among neighbours. Individual plants varied greatly in their male fecundity. Nectar concentration, a key feature of nectar that determines its profitability, was subjected to stabilizing selection. Selection through male function also affected corolla area (positive directional selection), corolla tube length (negative directional selection), and floral display size (stabilizing selection), but none of these traits were phenotypically correlated with nectar characteristics. Because nectar concentration affects the ability and foraging efficiency of different flower visitors to feed on nectar, stabilizing selection may reflect either the preference of the most effective pollinators, or antagonistic selection driven by pollinators and non-pollinating nectar consumers.
Fil: Gleiser, Gabriela Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación en Biodiversidad y Medioambiente; Argentina. University of Neuchâtel; Suiza
Fil: Internicola, Antonina I.. University of Neuchâtel; Suiza
Fil: Austerlitz, Frédéric. Centre National de la Recherche Scientifique; Francia
Fil: Bernasconi, Giorgina. University of Neuchâtel; Suiza
Subject
Nectar concentration
Petunia axillaris
Pollen dispersal
Seed paternity
Selection gradients
Stabilizing selection
Genética y Herencia
Ciencias Biológicas
CIENCIAS NATURALES Y EXACTAS
Biología Reproductiva
Ciencias Biológicas
CIENCIAS NATURALES Y EXACTAS
Biología
Ciencias Biológicas
CIENCIAS NATURALES Y EXACTAS
Access level
Restricted access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/11724