Abstract Detail



Functional Genetics/Genomics

Adhikari, Binaya [1], Caruso, Christina [2], Case, Andrea [3].

Diversity and complexity of sex-determining genetics in a gynodioecious wildflower Lobelia siphilitica L. (Campanulaceae).

Cytoplasmic male sterility (CMS) represents an interesting example of cytonuclear incompatibility in flowering plants. CMS genes are mitochondrial and can cause male (pollen) sterility unless one or more specific nuclear restorer alleles suppress them. Models propose that co-occurrence of multiple CMS types results in expression of female phenotypes in populations. However, the levels of CMS diversity within a gynodioecious species and its populations remain unclear. Also, whether CMS genes are selectively maintained or frequently replaced in a population is not clear. We conducted an extensive crossing experiment using 30 maternal families from 12 populations of a gynodioecious wildflower (Lobelia siphilitica) to estimate the diversity and distribution of CMS genes and to assess genetic models of male fertility restoration. We found at least six CMS types at the level of the species and 2–4 unique CMS types within some populations; this is higher than the diversity previously reported in any gynodioecious species. Most of these CMS types were widely distributed among populations, indicating that they may have been maintained within the species for a long time. Moreover, many CMS types had complex genetics of restoration involving multiple loci and sometimes epistasis. Finally, some of the CMS types were difficult to restore, suggesting that they either have complex restoration genetics or were formed relatively recently. Such CMS types could contribute to very high female frequencies in some populations.


1 - Kent State University, Biological Sciences, Cunningham Hall, Biological Sciences, Kent, OH, 44242, United States
2 - University Of Guelph, Department Of Integrative Biology, Guelph, ON, N1G 2W1, Canada
3 - Box 5190, 256 Cunningham Hall, Kent, OH, 44242, United States

Keywords:
Lobelia siphilitica
gynodioecy
Cytoplasmic Male Sterility.

Presentation Type: Oral Paper
Number: 0008
Abstract ID:279
Candidate for Awards:Margaret Menzel Award


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