GENETIC CONSEQUENCES OF RARITY IN ASTER FURCATUS (ASTERACEAE), A THREATENED, SELF-INCOMPATIBLE PLANT

Area of Science:

• Botany
• Conservation Genetics
• Plant Reproductive Biology

Background:

• Aster furcatus is a rare plant species with limited populations.
• Understanding its breeding system and genetic diversity is vital for conservation efforts.

Purpose of the Study:

• To verify the self-incompatibility of Aster furcatus.
• To assess the genetic variation and population structure of A. furcatus.
• To understand the implications of its breeding system and genetic diversity for conservation.

Main Methods:

• Conducted experimental self- and cross-pollinations to confirm self-incompatibility.
• Analyzed genetic variation at 22 electrophoretic loci across 23 populations.
• Examined subpopulation genetic structure using F statistics.

Main Results:

• Confirmed self-incompatibility in Aster furcatus through pollination experiments.
• Observed extremely low overall genetic diversity, with most loci fixed for single alleles.
• The triosephosphate isomerase (TPI-1) locus showed heterozygote excess, indicating outcrossing.
• Genetic variation at the TPI locus was largely due to differentiation among populations.

Conclusions:

• Aster furcatus is a self-incompatible, outcrossing species with critically low genetic diversity.
• Population differentiation is a significant factor in the limited genetic variation observed.
• The findings highlight the need for targeted conservation strategies for rare, self-incompatible plants.