Abstract

Mate choice in plants is poorly understood, in particular its indirect genetic benefits, but also the direct benefits of avoiding harmful matings. In the herbCollinsia heterophylla, delayed stigma receptivity has been suggested to enhance pollen competition, potentially functioning as a female mate choice trait. Previous studies show that this trait can mitigate the cost of early fertilization caused by pollen, thus providing a direct benefit. We performed two-donor pollinations during successive floral stages to assess how this stigma receptivity trait and two pollen traits known to affect siring success influence indirect benefits in terms of offspring performance. We also investigated differential resource allocation by studying the influence of sibling performance in the same capsule. Offspring performance in terms of flower number was mainly affected by parental identities and differential resource allocation. Offspring seed production showed some influence of resource allocation, but was also affected by pollen donor identity and varied positively with late stigma receptivity. However, the effect of late stigma receptivity on offspring seed production was weakened in matings with pollen that advanced stigma receptivity. In conclusion, delayed stigma receptivity may be selected through both direct and indirect fitness effects inC. heterophylla, where pollen-based delay on stigma receptivity might act as a cue for mate choice. However, selection may also be counteracted by antagonistic selection on pollen to advance stigma receptivity. Our results highlight the challenges of studying indirect genetic benefits and other factors that influence mate choice in plants.

Keywords

indirect benefit; pollen tube growth rate; resource allocation; sexual selection and conflict; stigma receptivity

Published in

Journal of Evolutionary Biology
2020, Volume: 33, number: 10, pages: 1452-1467
Publisher: WILEY

SLU Authors

• Lankinen, Åsa

  • Department of Plant Protection Biology, Swedish University of Agricultural Sciences
    
  • Lund University

UKÄ Subject classification

Evolutionary Biology
Ecology


Publication identifier

DOI: https://doi.org/10.1111/jeb.13684

Permanent link to this page (URI)

https://res.slu.se/id/publ/107792