![Journal cover image](https://secure.syndetics.com/index.aspx?isbn=/lc.gif&issn=0168-9525&client=dukeuniv)
The evolutionary dynamics of self-incompatibility systems.
Self-incompatible flowering plants reject pollen that expresses the same mating specificity as the pistil (female reproductive tract). In most plant families, pollen and pistil mating specificities segregate as a single locus, the S locus. In at least two self-incompatibility systems, distinct pollen and pistil specificity genes are embedded in an extensive nonrecombining tract. To facilitate consideration of how new S locus specificities arise in systems with distinct pollen and pistil genes, we present a graphical model for the generation of hypotheses. It incorporates the evolutionary principle that nonreciprocal siring success (cross-pollinations between two plants produce seeds in only one direction) tends to favor the rejecting partner. This model suggests that selection within S-allele specificity classes could accelerate the rate of nonsynonymous (amino acid-changing) substitutions, with periodic selective sweeps removing segregating variation within classes. Accelerated substitution within specificity classes could also promote the origin of new S-allele specificities.
Duke Scholars
Published In
DOI
ISSN
Publication Date
Volume
Issue
Start / End Page
Related Subject Headings
- Signal Transduction
- Reproduction
- Pollen
- Plants
- Models, Genetic
- Flowers
- Evolution, Molecular
- Developmental Biology
- Alleles
- 42 Health sciences
Citation
![Journal cover image](https://secure.syndetics.com/index.aspx?isbn=/lc.gif&issn=0168-9525&client=dukeuniv)
Published In
DOI
ISSN
Publication Date
Volume
Issue
Start / End Page
Related Subject Headings
- Signal Transduction
- Reproduction
- Pollen
- Plants
- Models, Genetic
- Flowers
- Evolution, Molecular
- Developmental Biology
- Alleles
- 42 Health sciences