Density-dependent self-fertilization and male versus hermaphrodite siring success in an androdioecious plant.

Details

Serval ID
serval:BIB_9BA11C2DAA1B
Type
Article: article from journal or magazin.
Collection
Publications
Title
Density-dependent self-fertilization and male versus hermaphrodite siring success in an androdioecious plant.
Journal
Evolution
Author(s)
Eppley S.M., Pannell J.R.
ISSN
0014-3820 (Print)
ISSN-L
0014-3820
Publication state
Published
Issued date
2007
Peer-reviewed
Oui
Volume
61
Number
10
Pages
2349-2359
Language
english
Abstract
Models of mating-system evolution emphasize the importance of frequency-dependent interactions among mating partners. It is also known that outcross siring success and the selfing rate in self-compatible hermaphrodites can be density dependent. Here, we use array experiments to show that the mating system (i.e., the outcrossing rate) and the siring success of morphs with divergent sex allocation strategies are both density dependent and frequency dependent in androdioecious populations of the wind-pollinated, annual plant Mercurialis annua. In particular, the outcrossing rate is a decreasing function of the mean interplant distance, regulated by a negative exponential pollen fall-off curve. Our results indicate that pollen dispersed from a male inflorescence are over 60% more likely to sire outcrossed progeny than equivalent pollen dispersed from hermaphrodites, likely due to the fact that males, but not hermaphrodites, disperse their pollen from erect inflorescence stalks. Because of this difference, and because males of M. annua produce much more pollen than hermaphrodites, the presence of males in the experimental arrays reduced both the selfing rate and the outcross siring success of hermaphrodites. We use our results to infer a density threshold below which males are unable to persist with hermaphrodites but above which they can invade hermaphroditic populations. We discuss our findings in the context of a metapopulation model, in which males can only persist in well-established populations but are excluded from small, sparse populations, for example, in the early stages of colonization.
Keywords
Biological Evolution, Disorders of Sex Development, Euphorbiaceae/genetics, Euphorbiaceae/physiology, Ploidies, Pollen, Population Density, Reproduction/physiology
Pubmed
Web of science
Open Access
Yes
Create date
20/09/2011 7:40
Last modification date
20/08/2019 15:02
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